diff --git a/day22/sol.py b/day22/sol.py
index afc8412..9e64ac6 100644
--- a/day22/sol.py
+++ b/day22/sol.py
@@ -38,7 +38,8 @@ def solve(f):
     check(data)
     settle(data)
     check(data)
-    disintegrate(data)
+    #disintegrate(data)
+    cascade(data)
 
 def settle(data):
     def zindex(b):
@@ -118,6 +119,43 @@ def disintegrate(data):
     return (t)
 
             
+def cascade(data):
+    print(*data, sep="\n")
+    t = 0
+
+    #for i,x in enumerate(data):
+    #    assert not canlower(x,data[:i])
+
+    for i,x in enumerate(data):
+        below = data[:i]
+        upper = data[i+1:]
+        moved = 0
+
+        if below:
+            top = max(z[1] for x,y,z in below) + 1
+        else:
+            top = 1
+        for b in upper:
+            # lower blocks one at a time
+            z = b[2][0]
+            if z > top:
+                b = lower(b, z-top)
+
+            while canlower(b, below):
+                b = lower(b)
+
+            if b[2][0] < z:
+                moved += 1
+
+            #print("lowering block %d by %d" % (i,n))
+            below.append(b)
+            top = max(top, b[2][1]+1)
+
+        print(i, x, "caused %d blocks to move" % moved)
+        t += moved
+
+    print(t)
+    return (t)
 
 def lower(brick, n=1):
     """lower a brick n spaces in the z direction"""