Landships II

8Hussar · Corporal

Canadian Armoured Autocar

CharlieC · Legend

I believe back then the acetylene would have been generated by dripping water onto Calcium Carbide. The Carbide lamps were self-contained and

had no external acetylene storage.

Acetylene really can't stored in a pressurised container since it explodes under pressure. What we call Acetylene cylinders

are acetylene absorbed into Acetone with the cylinder filled a porous material like crushed firebrick.

At a guess the smaller container on the Autocar was probably oil - before cast iron piston rings in the 1920s engines consumed vast amounts of oil.

Charlie

8Hussar · Corporal

Thank you that does make sense. There is a question. however, because if you study the photos of the cars in action and training you will notice a line going from the large headlamp in through the frontal armour to the inside. I noticed a similar thing with the Minerva Armoured Car and it apparently has some sort of generator (a small box really) mounted on the outside and hooked up to the lamp. Maybe I have got the acetylene bit wrong and it is another chemical? Any further thoughts?

CharlieC · Legend

That sounds right for an acetylene generator remote from the light. Having a seperate generator

makes sense since the reaction tends to be fairly messy with spattered calcium oxide.

The process for making industrial amounts of Calcium Carbide was invented in 1892 and the product

is quite stable provided it's kept in anhydrous conditions.

Charlie

8Hussar · Corporal

Thank you. Your comment about oil usage is certainly true. I was speaking with the workshop staff that took the Armoured Autocar to Mons in 2018 it was mentioned that it used a terrific amount of oil. In fact the comment was - when the engine stopped smoking it was time to add more oil. I am still intrigued about the smaller container mounted to the left hand side wall beside the petrol reservoir. There is no tube or hole in the container at all in the side or bottom but the top was bolted on and it is missing. I assume if it was oil it would be gravity fed, hence the need for a tube or at least the remnants of a opening in the bottom or lower side of the container. That leads me to consider it could have been the carbide generator as the gas was disbursed from the top - which is conveniently missing. Thoughts?

Don

CharlieC · Legend

If you look a vintage acetylene generators on a web search they are pretty much all

the same pattern. There's a lower container which held the carbide and an upper water container

which was attached with clamps or similar. The upper container held water and had a valve to control

the water flow to the lower container. There were one or more gas pipes which went through the water

tank for the acetylene. It sounds as if your example has only the lower container.

Charlie

8Hussar · Corporal

Thanks for the information I think you may be correct. Sadly, there does not appear to be any period interior photos to confirm this. I have checked out many of the existing US made carbide generators and your description certainly fits. Thank you again for your help. That elusive photo confirmation - the story of modelling.

Cheers!

Don