UPD text -- about memory addresses

Explain the first available address in the dictionary (by `here`).

See-also: skilldrick#14

Author: ruv

index.markdown

@@ -560,8 +560,9 @@ stack:
 
 {% include editor.html size="small"%}
 
-You should see the value `1000` on the stack. This Forth implementation arbitrarily
-starts storing variables at the memory location `1000`.
+You should see an address (some value like `1577`) on the stack. This Forth implementation arbitrarily
+starts storing variables at the memory location `1000`,
+and the internal variables and buffers already take up some space.
 
 The word `!` stores a value at the memory location referenced by a variable, and the
 word `@` fetches the value from a memory location: