diff --git a/src/com/lushprojects/circuitjs1/client/CompositeElm.java b/src/com/lushprojects/circuitjs1/client/CompositeElm.java
index 9bc1bc72..1009462b 100644
--- a/src/com/lushprojects/circuitjs1/client/CompositeElm.java
+++ b/src/com/lushprojects/circuitjs1/client/CompositeElm.java
@@ -207,7 +207,7 @@ public String dumpElements(int mask) {
     }
 
     // are n1 and n2 connected internally somehow?
-    public boolean getConnection(int n1, int n2) {
+    public boolean getConnectionSlow(int n1, int n2) {
 	Vector<Integer> connectedNodes = new Vector<Integer>();
 
 	// keep list of nodes connected to n1
@@ -242,8 +242,35 @@ public boolean getConnection(int n1, int n2) {
 	return false;
     }
     
+    HashMap<IntPair, Boolean> connectionMap;
+    HashMap<Integer, Boolean> groundConnectionMap;
+
+    public boolean getConnection(int n1, int n2) {
+	if (connectionMap == null)
+	    connectionMap = new HashMap<IntPair, Boolean>();
+	IntPair key = new IntPair(n1, n2);
+	Boolean result = connectionMap.get(key);
+	if (result != null)
+	    return result;
+	result = getConnectionSlow(n1, n2);
+	connectionMap.put(key, result);
+	return result;
+    }
+
     // is n1 connected to ground somehow?
     public boolean hasGroundConnection(int n1) {
+	if (groundConnectionMap == null)
+	    groundConnectionMap = new HashMap<Integer, Boolean>();
+	Integer key = n1;
+	Boolean result = groundConnectionMap.get(key);
+	if (result != null)
+	   return result;
+	result = hasGroundConnectionSlow(n1);
+	groundConnectionMap.put(key, result);
+	return result;
+    }
+
+    public boolean hasGroundConnectionSlow(int n1) {
 	Vector<Integer> connectedNodes = new Vector<Integer>();
 
 	// keep list of nodes connected to n1