Hi all
This was a Chevrolet invention, namely a Smoke Screen Generator and was primarily designed for the following purposes;
* to hide the truck on a battlefield (unfortunately all the enemy had to do was aim at the smoke)
* to hide the identity of a person who actually owned a Chevrolet
* to use at a disco
I believe there were other reasons as well but they escape me for the moment, but I am sure others will remember them.
Bob