diff --git a/learn-physics.cabal b/learn-physics.cabal
--- a/learn-physics.cabal
+++ b/learn-physics.cabal
@@ -1,5 +1,5 @@
 Name:                learn-physics
-Version:             0.4
+Version:             0.4.1
 Synopsis:            Haskell code for learning physics
 Description:         A library of functions for vector calculus,
                      calculation of electric field, electric flux,
@@ -36,7 +36,7 @@
   Build-depends:       base >= 4.2 && < 4.8,
                        vector-space >= 0.8.4 && < 0.9,
                        not-gloss >= 0.5.0.4 && < 0.7,
-                       spatial-math >= 0.1.7 && < 0.3,
+                       spatial-math >= 0.1.7 && < 0.2,
                        gnuplot >= 0.5 && < 0.6
   Hs-source-dirs:      src