Here is something I found:
"One of the most interesting of these early experimental tanks was the HA 36, a one-man tank similar in appearance to, but much smaller than, the British heavy tanks. Constructed under the supervision of L.H. Thoen at the Stockton plant of the Holt Company, it was powered by a motorcycle engine operating through a special transmission. The tracks were made up of Link Belt 44 chain on which were bolted wood cleats. Although the tank gave the appearance of being armed and armored, it was neither."
Tanks and Armored Vehicles by Lt. Col. Robert J. Icks, Edited by Phillip Andrews; Duell, Sloan and Pearce publishers; copyright 1945
The last sentence is the key here I believe. This by the way is a great book to find. The information is not entirely correct (as we know it nowadays), but it contains some of the neatest photos I have ever seen. I attribute that to the fact it was printed in 1945, and the photos hadn't had a chance to get lost!
By the way, did you notice the author's name? Along with a rank? I found that interesting.