I know that several of you have dealt with this question before and have the 
answer already.   I was asked what was the significance of the crescent moon 
design on privies.   I was given a number of options:

1. It was a symbol denoting Islamic origins

2. It originated in the Civil War in Louisiana

3. The structure doubled as an astronomical observatory
 
4. None of the above

I suspect that the answer is #4.   Can anyone give me an accurate reply?

RLH