diff --git a/math32.tal b/math32.tal
index 3669622..977e94e 100644
--- a/math32.tal
+++ b/math32.tal
@@ -1,5 +1,6 @@
 ( math32.tal )
 ( )
+( This library supports arithmetic on 32-bit unsigned integers. )
 ( 32-bit integers are represented by two 16-bit integers )
 ( x** means xhi* xlo* )
 
@@ -7,7 +8,6 @@
 %RTN  { JMP2r }
 %TOR { ROT ROT } ( a b c -> c a b )
 %TOR2 { ROT2 ROT2 }
-%POP4 { POP2 POP2 }
 %COMPLEMENT32 { SWP2 #ffff EOR2 SWP2 #ffff EOR2 } )
 
 ( bitcount: number of bits needed to represent number )
diff --git a/test-math32.tal b/test-math32.tal
index 563472f..c876981 100644
--- a/test-math32.tal
+++ b/test-math32.tal
@@ -1,7 +1,6 @@
-( math32.tal )
+( test-math32.tal )
 ( )
-( 32-bit integers are represented by two 16-bit integers )
-( x** means xhi* xlo* )
+( methods for testing math32 and emitting output )
 
 %EMIT { #18 DEO } )
 %DIGIT { #00 SWP ;digits ADD2 LDA EMIT }