Back in the late 50s or early 60s I had my car in for a muffler replacement. The mechanics had recently replaced a muffler on a car that was bought in California. When they cut it loose it hit the floor like a concrete block. When they examined it they found it was filled with sand and weighed about 40 pounds. The owner, who was recently discharged from the service said it was a California sandy. Has anyone else heard of this or was it the invention of some fertile mind?