touchstone: cannot rub on the stone gold

hack around the silly grammar

src/invent.c

@@ -714,6 +714,7 @@ register const char *let,*word;
 	boolean usegold = FALSE;	/* can't use gold because its illegal */
 	boolean allowall = FALSE;
 	boolean allownone = FALSE;
+	boolean touchstone = FALSE;
 	xchar foox = 0;
 	long cnt;
 	boolean prezero = FALSE;
@@ -727,14 +728,14 @@ register const char *let,*word;
 	if(*let == GOLD_CLASS) let++, usegold = TRUE;
 #endif
 	/* Ugly check for touchstone */
-	if (!strncmp(word, "rub on", 6)
+	if (!strncmp(word, "rub on", 6)) {
+	    touchstone = TRUE;		/* avoid silly "stone gold" */
 #ifndef GOLDOBJ
-		&& u.ugold)
-		allowgold = usegold = TRUE;
+	    if(u.ugold) allowgold = usegold = TRUE;
 #else
-		)
-		usegold = TRUE;		
+	    usegold = TRUE;
 #endif
+	}
 
 	/* Equivalent of an "ugly check" for gold */
 	if (usegold && !strcmp(word, "eat") && !metallivorous(youmonst.data))
@@ -917,9 +918,12 @@ register const char *let,*word;
 			return(allownone ? &zeroobj : (struct obj *) 0);
 		}
 		if(ilet == def_oc_syms[GOLD_CLASS]) {
-			if(!usegold){
+			if (!usegold) {
+			    if (touchstone)
+				You("cannot rub gold on the stone.");
+			    else
 				You("cannot %s gold.", word);
-				return(struct obj *)0;
+			    return(struct obj *)0;
 #ifndef GOLDOBJ
 			} else if (!allowgold) {
 				You("are not carrying any gold.");