diff --git a/Project.toml b/Project.toml
index 1f12c7ba..12497280 100644
--- a/Project.toml
+++ b/Project.toml
@@ -38,9 +38,10 @@ julia = "1.6"
 Calculus = "49dc2e85-a5d0-5ad3-a950-438e2897f1b9"
 DiffTests = "de460e47-3fe3-5279-bb4a-814414816d5d"
 InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
+Measurements = "eff96d63-e80a-5855-80a2-b1b0885c5ab7"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Calculus", "DiffTests", "SparseArrays", "StaticArrays", "Test", "InteractiveUtils"]
+test = ["Calculus", "DiffTests", "SparseArrays", "StaticArrays", "Test", "InteractiveUtils", "Measurements"]
diff --git a/src/partials.jl b/src/partials.jl
index a5316e3e..ddec4ebc 100644
--- a/src/partials.jl
+++ b/src/partials.jl
@@ -7,7 +7,7 @@ end
 ##############################
 
 @generated function single_seed(::Type{Partials{N,V}}, ::Val{i}) where {N,V,i}
-    ex = Expr(:tuple, [ifelse(i === j, :(one(V)), :(zero(V))) for j in 1:N]...)
+    ex = Expr(:tuple, [ifelse(i === j, :(oneunit(V)), :(zero(V))) for j in 1:N]...)
     return :(Partials($(ex)))
 end
 
diff --git a/test/MiscTest.jl b/test/MiscTest.jl
index 0ed8039a..cb5b0ef3 100644
--- a/test/MiscTest.jl
+++ b/test/MiscTest.jl
@@ -6,6 +6,7 @@ using Test
 using ForwardDiff
 using DiffTests
 using SparseArrays: sparse
+using Measurements: Measurements
 
 include(joinpath(dirname(@__FILE__), "utils.jl"))
 
@@ -161,4 +162,9 @@ end
 # example from https://github.com/JuliaDiff/DiffRules.jl/pull/98#issuecomment-1574420052
 @test only(ForwardDiff.hessian(t -> abs(t[1])^2, [0.0])) == 2
 
+#issue 651, using Measurements
+#one(x::Measurement{T}) where T = one(T) != oneunit(x)
+f651(x) = 2.1*x + 1
+@test ForwardDiff.derivative(f651,Measurements.measurement(1.0, 0.001)) == 2.1
+
 end # module