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  <xsd:element abstract="true" id="hrzn_EnergyEfficiencyMember" name="EnergyEfficiencyMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_EquityPurchaseAgreementMember" name="EquityPurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_EquitySalesAgreementMaximumValue" name="EquitySalesAgreementMaximumValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_EquitySalesAgreementRemainingAmountAvailableForIssuance" name="EquitySalesAgreementRemainingAmountAvailableForIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_EstimatedTimeToExitMember" name="EstimatedTimeToExitMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAppreciationDepreciationIncludedInEarnings" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAppreciationDepreciationIncludedInEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOtherPeriodIncreaseDecrease" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOtherPeriodIncreaseDecrease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaymentInkindInterest" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaymentInkindInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRealizedGainLossIncludedInEarnings" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRealizedGainLossIncludedInEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersBetweenInvestments" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersBetweenInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetWarrantsAndEquityReceived" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetWarrantsAndEquityReceived" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_FederalExciseTaxPercent" name="FederalExciseTaxPercent" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_FourInvestmentsMember" name="FourInvestmentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_GTMedicalTechnologiesIncMember" name="GTMedicalTechnologiesIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_GlassRoutesLLCMember" name="GlassRoutesLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HIMVLLCMember" name="HIMVLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HavenlyIncMember" name="HavenlyIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HiveMQIncMember" name="HiveMQIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HorizonTechnologyFinanceCorporationMember" name="HorizonTechnologyFinanceCorporationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HyperfineIncMember" name="HyperfineIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_HypotheticalMarketYieldMember" name="HypotheticalMarketYieldMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_IncentiveFeeCapAndDeferralMechanismContingentFutureLiability" name="IncentiveFeeCapAndDeferralMechanismContingentFutureLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_IncentiveFeeCapAndDeferralMechanismReductionToExpense" name="IncentiveFeeCapAndDeferralMechanismReductionToExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_IncentiveFeeToPreincentiveNetInvestmentIncome" name="IncentiveFeeToPreincentiveNetInvestmentIncome" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_IncreaseDecreaseInEndoftermPayments" name="IncreaseDecreaseInEndoftermPayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_IncreaseDecreaseInUnearnedIncome" name="IncreaseDecreaseInUnearnedIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_InfobionicIncMember" name="InfobionicIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_InterestAndFeeIncomeMember" name="InterestAndFeeIncomeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_InternetAndMediaSectorMember" name="InternetAndMediaSectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentAssetsMeasurementInput" name="InvestmentAssetsMeasurementInput" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentCompanyAverageDebtPerShare" name="InvestmentCompanyAverageDebtPerShare" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyDistributionToShareholdersPerShareNetInvestmentIncome" name="InvestmentCompanyDistributionToShareholdersPerShareNetInvestmentIncome" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyDistributionToShareholdersPerShareNetRealizedGainOnInvestments" name="InvestmentCompanyDistributionToShareholdersPerShareNetRealizedGainOnInvestments" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentCompanyDistributionToShareholdersPerShareOther" name="InvestmentCompanyDistributionToShareholdersPerShareOther" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyIncentiveFeePayableExpired" name="InvestmentCompanyIncentiveFeePayableExpired" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyInvestmentDepreciationAppreciationPerShare" name="InvestmentCompanyInvestmentDepreciationAppreciationPerShare" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyInvestmentIncomeLossRatioAfterIncentiveAllocationExcludingVoluntaryFeeWaiver" name="InvestmentCompanyInvestmentIncomeLossRatioAfterIncentiveAllocationExcludingVoluntaryFeeWaiver" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyInvestmentIncomeNet" name="InvestmentCompanyInvestmentIncomeNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyNetAssetValuePerSharePeriodIncreaseDecreaseDiluted" name="InvestmentCompanyNetAssetValuePerSharePeriodIncreaseDecreaseDiluted" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentCompanyPortfolioTurnoverRatio" name="InvestmentCompanyPortfolioTurnoverRatio" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_InvestmentConcentrationRiskMember" name="InvestmentConcentrationRiskMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentIncomeAttributableToNoncashPaidinkindInterestPercent" name="InvestmentIncomeAttributableToNoncashPaidinkindInterestPercent" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentIncomeNetOfExciseTax" name="InvestmentIncomeNetOfExciseTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentIncomePrepaymentFee" name="InvestmentIncomePrepaymentFee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentInterestBasisSpreadVariableRate" name="InvestmentInterestBasisSpreadVariableRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_InvestmentManagementAgreementMember" name="InvestmentManagementAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentNonaccrualIncomeNotReceivedInCashPercent" name="InvestmentNonaccrualIncomeNotReceivedInCashPercent" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentOwnedCeilingRate" name="InvestmentOwnedCeilingRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentOwnedEndOfTermPaymentsETP" name="InvestmentOwnedEndOfTermPaymentsETP" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentsCostNonaccrualStatus" name="InvestmentsCostNonaccrualStatus" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentsFairValueNonaccrualStatus" name="InvestmentsFairValueNonaccrualStatus" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_InvestmentsInAndAdvancesToAffiliatesAtFairValueDiscountAccretion" name="InvestmentsInAndAdvancesToAffiliatesAtFairValueDiscountAccretion" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentsInAndAdvancesToAffiliatesAtFairValueTransfers" name="InvestmentsInAndAdvancesToAffiliatesAtFairValueTransfers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentsInMoneyMarketFundsAcquiredInMerger" name="InvestmentsInMoneyMarketFundsAcquiredInMerger" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_InvestmentsNonaccrualInterestIncome" name="InvestmentsNonaccrualInterestIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_JointVentureInvestmentFundsMember" name="JointVentureInvestmentFundsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_June302026ExpirationMember" name="June302026ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_June302027ExpirationMember" name="June302027ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_June302028ExpirationMember" name="June302028ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_KeyFacilityMember" name="KeyFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_LastEquityFinancingMember" name="LastEquityFinancingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_LiabilitiesAndNetAssets" name="LiabilitiesAndNetAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_LineOfCreditFacilityAdvanceRate" name="LineOfCreditFacilityAdvanceRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_LineOfCreditFacilityAdvanceRateOfEligibleDebtInvestments" name="LineOfCreditFacilityAdvanceRateOfEligibleDebtInvestments" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_LineOfCreditFacilityChangeInMaximumBorrowingCapacity" name="LineOfCreditFacilityChangeInMaximumBorrowingCapacity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_LineOfCreditFacilityMaximumBorrowingCapacityAccordianFeature" name="LineOfCreditFacilityMaximumBorrowingCapacityAccordianFeature" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_LineOfCreditFacilityMaximumBorrowingCapacityAccordionFeature" name="LineOfCreditFacilityMaximumBorrowingCapacityAccordionFeature" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_LongGrovePharmaceuticalLLCMember" name="LongGrovePharmaceuticalLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MMLUSIncMember" name="MMLUSIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MRCCMember" name="MRCCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MRCCMergerMember" name="MRCCMergerMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_March312027ExpirationMember" name="March312027ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_March312028ExpirationMember" name="March312028ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_March312029ExpirationMember" name="March312029ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MasteryPrepLLCMember" name="MasteryPrepLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MeasurementInputHypotheticalMarketYieldsMember" name="MeasurementInputHypotheticalMarketYieldsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MedicalDeviceSectorMember" name="MedicalDeviceSectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MergerAgreementFeeWaiverMember" name="MergerAgreementFeeWaiverMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MirantisIncMember" name="MirantisIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MomentumUSBidcoLLCMember" name="MomentumUSBidcoLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MonroeCapitalIntermediateHoldingsLLCMember" name="MonroeCapitalIntermediateHoldingsLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MultipleProbabilityWeightedCashFlowModelMember" name="MultipleProbabilityWeightedCashFlowModelMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_MultipleProbabilityWeightedScenarioModelMember" name="MultipleProbabilityWeightedScenarioModelMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_NYLFacilityMember" name="NYLFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_NetAssets" name="NetAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_NetworkingSectorMember" name="NetworkingSectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_NuveenFacilityMember" name="NuveenFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M101DividendsMember" name="O2025M101DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M102DividendsMember" name="O2025M102DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M103DividendsMember" name="O2025M103DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M21DividendsMember" name="O2025M21DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M22DividendsMember" name="O2025M22DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M23DividendsMember" name="O2025M23DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M41DividendsMember" name="O2025M41DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M42DividendsMember" name="O2025M42DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M43DividendsMember" name="O2025M43DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M72DividendsMember" name="O2025M72DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M73DividendsMember" name="O2025M73DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2025M7DividendsMember" name="O2025M7DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M10DividendsMember" name="O2026M10DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M11DividendsMember" name="O2026M11DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M22DividendsMember" name="O2026M22DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M23DividendsMember" name="O2026M23DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M3DividendsMember" name="O2026M3DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M51DividendsMember" name="O2026M51DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M52DividendsMember" name="O2026M52DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M53DividendsMember" name="O2026M53DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M54DividendsMember" name="O2026M54DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M55DividendsMember" name="O2026M55DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M56DividendsMember" name="O2026M56DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_O2026M9DividendsMember" name="O2026M9DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OneInvestmentMember" name="OneInvestmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OnkosSurgicalIncMember" name="OnkosSurgicalIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OssioIncMember" name="OssioIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OtherHealthcareSectorMember" name="OtherHealthcareSectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OtherInvestmentMember" name="OtherInvestmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_OtherSustainabilitySectorMember" name="OtherSustainabilitySectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_OwnershipPercentageAcquired" name="OwnershipPercentageAcquired" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="hrzn_PelthosTherapeuticsIncMember" name="PelthosTherapeuticsIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PerformanceBasedIncentiveFee" name="PerformanceBasedIncentiveFee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_PhigenicsHoldingsIncMember" name="PhigenicsHoldingsIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_PolicyTable" name="PolicyTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PreincentiveFeeNetInvestmentIncomeCatchupPercent" name="PreincentiveFeeNetInvestmentIncomeCatchupPercent" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PreincentiveFeeNetInvestmentIncomeHurdleRate" name="PreincentiveFeeNetInvestmentIncomeHurdleRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PreincentiveFeeNetInvestmentIncomeHurdleRateAnnualized" name="PreincentiveFeeNetInvestmentIncomeHurdleRateAnnualized" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PreincentiveFeeNetInvestmentIncomeMaximumRateToTriggerCatchup" name="PreincentiveFeeNetInvestmentIncomeMaximumRateToTriggerCatchup" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_PreincentiveFeeNetInvestmentIncomeMaximumRateToTriggerCatchupAnnualized" name="PreincentiveFeeNetInvestmentIncomeMaximumRateToTriggerCatchupAnnualized" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_ProbabilityWeightingMember" name="ProbabilityWeightingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_ProceedsFromDebtSecuritiesEndoftermAmount" name="ProceedsFromDebtSecuritiesEndoftermAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_RealizedGainlossExtinguishmentOfDebt" name="RealizedGainlossExtinguishmentOfDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_RealizedInvestmentGainsLossesNetOfDebtExtinguishment" name="RealizedInvestmentGainsLossesNetOfDebtExtinguishment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_RefinancedDebtInvestmentBalances" name="RefinancedDebtInvestmentBalances" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_RoHoCapitalOpportunityLLCMember" name="RoHoCapitalOpportunityLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_S2026M10DividendsMember" name="S2026M10DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_S2026M11DividendsMember" name="S2026M11DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_S2026M9DividendsMember" name="S2026M9DividendsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SambaTVIncMember" name="SambaTVIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SelectedInterestRatesDailyMember" name="SelectedInterestRatesDailyMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_September302026ExpirationMember" name="September302026ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_September302027ExpirationMember" name="September302027ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_September302028ExpirationMember" name="September302028ExpirationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SoftwareHealthcareInformationAndServiceMember" name="SoftwareHealthcareInformationAndServiceMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SoftwareSectorMember" name="SoftwareSectorMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SonexHealthIncMember" name="SonexHealthIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SparkchargeIncMember" name="SparkchargeIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_StarComplianceMidcoLLCMember" name="StarComplianceMidcoLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_StellarCyberIncMember" name="StellarCyberIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_StockRepurchaseProgramMaximumPercentageOfNetAssetValue" name="StockRepurchaseProgramMaximumPercentageOfNetAssetValue" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_StockRepurchaseProgramPercentageOfOutstandingStockMaximum" name="StockRepurchaseProgramPercentageOfOutstandingStockMaximum" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="hrzn_StockRepurchaseProgramPolicyTextBlock" name="StockRepurchaseProgramPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_StockRepurchasedDuringPeriodPerShare" name="StockRepurchasedDuringPeriodPerShare" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_SupplyNetworkVisibilityHoldingsLLCMember" name="SupplyNetworkVisibilityHoldingsLLCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2023EquityDistributionAgreementMember" name="The2023EquityDistributionAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2026NotesMember" name="The2026NotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2026NotesUnderwriterOptionMember" name="The2026NotesUnderwriterOptionMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2027NotesMember" name="The2027NotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2027NotesUnderwriterOptionMember" name="The2027NotesUnderwriterOptionMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2028NotesMember" name="The2028NotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2030ConvertibleNotesMember" name="The2030ConvertibleNotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The2031ConvertibleNotesMember" name="The2031ConvertibleNotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_The625NotesDue2027Member" name="The625NotesDue2027Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_ThreeInvestmentsMember" name="ThreeInvestmentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_ThreeYearICurveMember" name="ThreeYearICurveMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_TreasuryRateMember" name="TreasuryRateMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_VoltBidcoIncMember" name="VoltBidcoIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_WarrantInvestmentsReceivedAndRecordedAsUnearnedIncome" name="WarrantInvestmentsReceivedAndRecordedAsUnearnedIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="hrzn_WarrantsReceivedInSettlementOfFeeIncome" name="WarrantsReceivedInSettlementOfFeeIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_ZeroInvestmentsMember" name="ZeroInvestmentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-consolidated-schedule-of-investments-investments-unaudited-2-details" name="statement-statement-consolidated-schedule-of-investments-investments-unaudited-2-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-consolidated-schedule-of-investments-investments-unaudited-details" name="statement-statement-consolidated-schedule-of-investments-investments-unaudited-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-consolidated-schedule-of-investments-investments-unaudited-details-parentheticals" name="statement-statement-consolidated-schedule-of-investments-investments-unaudited-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-consolidated-schedule-of-investments-unaudited-tables" name="statement-statement-consolidated-schedule-of-investments-unaudited-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-10-distributions-distribution-activity-details" name="statement-statement-note-10-distributions-distribution-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-10-distributions-tables" name="statement-statement-note-10-distributions-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-11-earnings-per-share-schedule-of-earnings-per-share-details" name="statement-statement-note-11-earnings-per-share-schedule-of-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-11-earnings-per-share-tables" name="statement-statement-note-11-earnings-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-12-financial-highlights-financial-highlights-details" name="statement-statement-note-12-financial-highlights-financial-highlights-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-12-financial-highlights-tables" name="statement-statement-note-12-financial-highlights-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-3-related-party-transactions-expiration-dates-of-contingent-future-liability-details" name="statement-statement-note-3-related-party-transactions-expiration-dates-of-contingent-future-liability-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-3-related-party-transactions-tables" name="statement-statement-note-3-related-party-transactions-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-4-investments-investments-details" name="statement-statement-note-4-investments-investments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-4-investments-schedule-of-summarized-financial-information-details" name="statement-statement-note-4-investments-schedule-of-summarized-financial-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-4-investments-tables" name="statement-statement-note-4-investments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-5-transactions-with-affiliated-companies-schedule-of-investments-in-affiliated-companies-2-details" name="statement-statement-note-5-transactions-with-affiliated-companies-schedule-of-investments-in-affiliated-companies-2-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-5-transactions-with-affiliated-companies-schedule-of-investments-in-affiliated-companies-details" name="statement-statement-note-5-transactions-with-affiliated-companies-schedule-of-investments-in-affiliated-companies-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-5-transactions-with-affiliated-companies-tables" name="statement-statement-note-5-transactions-with-affiliated-companies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-6-fair-value-assets-at-fair-value-on-a-recurring-basis-details" name="statement-statement-note-6-fair-value-assets-at-fair-value-on-a-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-6-fair-value-reconciliation-of-level-3-assets-measured-on-a-recurring-basis-details" name="statement-statement-note-6-fair-value-reconciliation-of-level-3-assets-measured-on-a-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-6-fair-value-significant-level-3-fair-value-measurement-inputs-details" name="statement-statement-note-6-fair-value-significant-level-3-fair-value-measurement-inputs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-6-fair-value-tables" name="statement-statement-note-6-fair-value-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-7-borrowings-borrowings-details" name="statement-statement-note-7-borrowings-borrowings-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-7-borrowings-tables" name="statement-statement-note-7-borrowings-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-8-financial-instruments-with-offbalancesheet-risk-tables" name="statement-statement-note-8-financial-instruments-with-offbalancesheet-risk-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-note-8-financial-instruments-with-offbalancesheet-risk-unfunded-commitments-details" name="statement-statement-note-8-financial-instruments-with-offbalancesheet-risk-unfunded-commitments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="hrzn_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
