diff --git a/broken-fact.rkt b/broken-fact.rkt
deleted file mode 100644
index e745c43..0000000
--- a/broken-fact.rkt
+++ /dev/null
@@ -1,10 +0,0 @@
-#lang planet dyoo/whalesong
-
-(define (f x)
-  (if (= x 0)
-      "one"
-      (* x (f (sub1 x)))))
-
-(f 0)
-(list (f 3)
-      (f 4))
diff --git a/scribblings/cs19.scrbl b/scribblings/cs19.scrbl
index dc75262..c4fb9e7 100644
--- a/scribblings/cs19.scrbl
+++ b/scribblings/cs19.scrbl
@@ -22,6 +22,16 @@
 
 @section{Installation}
 
+Racket 5.1.2 or greater is a prerequisite for Whalesong.  Brown CS
+maintains their own install for 5.1.3 in
+@filepath{/local/projects/racket/releases/5.1.3/bin/}.
+shell, you can add:
+@verbatim|{
+pathprependifdir PATH "/local/projects/racket/releases/5.1.3/bin"    
+}|
+to your @filepath{.environment}.
+
+
 We'll install a local development copy of Whalesong in a @filepath{whalesong} subdirectory.
 On the very first time we install Whalesong:
 @verbatim|{