diff --git a/src/dim2/mat2.rs b/src/dim2/mat2.rs
index c257d2ed..ff682b5a 100644
--- a/src/dim2/mat2.rs
+++ b/src/dim2/mat2.rs
@@ -87,7 +87,7 @@ impl<T:Copy + Add<T, T> + Mul<T, T>> LMul<Vec2<T>> for Mat2<T>
   }
 }
 
-impl<T:Copy + Mul<T, T> + Quot<T, T> + Sub<T, T> + Neg<T> + Eq + Zero>
+impl<T:Copy + Mul<T, T> + Quot<T, T> + Sub<T, T> + Neg<T> + Zero>
 Inv for Mat2<T>
 {
   fn inverse(&self) -> Mat2<T>
@@ -103,7 +103,7 @@ Inv for Mat2<T>
   {
     let det = self.m11 * self.m22 - self.m21 * self.m12;
 
-    assert!(det != Zero::zero());
+    assert!(!det.is_zero());
 
     *self = Mat2(self.m22 / det , -self.m12 / det,
                  -self.m21 / det, self.m11 / det)
diff --git a/src/dim2/vec2.rs b/src/dim2/vec2.rs
index 2a251b1e..b6a89ac1 100644
--- a/src/dim2/vec2.rs
+++ b/src/dim2/vec2.rs
@@ -2,6 +2,7 @@ use core::num::{Zero, Algebraic};
 use traits::dot::Dot;
 use traits::dim::Dim;
 use traits::cross::Cross;
+use dim1::vec1::Vec1;
 
 #[deriving(Eq)]
 pub struct Vec2<T>
@@ -43,10 +44,10 @@ impl<T:Copy + Mul<T, T> + Add<T, T> + Algebraic> Dot<T> for Vec2<T>
   { self.sqnorm().sqrt() }
 }
 
-impl<T:Copy + Mul<T, T> + Sub<T, T>> Cross<T> for Vec2<T>
+impl<T:Copy + Mul<T, T> + Sub<T, T>> Cross<Vec1<T>> for Vec2<T>
 {
-  fn cross(&self, other : &Vec2<T>) -> T
-  { self.x * other.y - self.y * other.x }
+  fn cross(&self, other : &Vec2<T>) -> Vec1<T>
+  { Vec1(self.x * other.y - self.y * other.x) }
 }
 
 impl<T:Copy + Neg<T>> Neg<Vec2<T>> for Vec2<T>
diff --git a/src/dim3/mat3.rs b/src/dim3/mat3.rs
index cc58a0c0..00fb0a80 100644
--- a/src/dim3/mat3.rs
+++ b/src/dim3/mat3.rs
@@ -104,8 +104,7 @@ impl<T:Copy + Add<T, T> + Mul<T, T>> LMul<Vec3<T>> for Mat3<T>
   }
 }
 
-impl<T:Copy + Mul<T, T> + Quot<T, T> + Sub<T, T> + Add<T, T> + Neg<T>
-     + Eq + Zero>
+impl<T:Copy + Mul<T, T> + Quot<T, T> + Sub<T, T> + Add<T, T> + Neg<T> + Zero>
 Inv for Mat3<T>
 {
   fn inverse(&self) -> Mat3<T>
@@ -127,7 +126,7 @@ Inv for Mat3<T>
               - self.m12 * minor_m21_m33
               + self.m13 * minor_m21_m32;
 
-    assert!(det != Zero::zero());
+    assert!(det.is_zero());
 
     *self = Mat3(
       (minor_m22_m33  / det),
diff --git a/src/nalgebra.rc b/src/nalgebra.rc
index 695f1e3d..27956944 100644
--- a/src/nalgebra.rc
+++ b/src/nalgebra.rc
@@ -13,6 +13,9 @@ pub use dim3::mat3::Mat3;
 pub use dim2::vec2::Vec2;
 pub use dim2::mat2::Mat2;
 
+pub use dim1::vec1::Vec1;
+pub use dim1::mat1::Mat1;
+
 pub use ndim::nvec::NVec;
 pub use ndim::nmat::NMat;
 
@@ -34,6 +37,12 @@ mod dim2
   mod mat2;
 }
 
+mod dim1
+{
+  mod vec1;
+  mod mat1;
+}
+
 mod dim3
 {
   mod vec3;