Scale approx. 1/20th.
The 19th century manual and steam fire engines did not carry a large supply of water so the chemical engine was introduced.
The actual model dates from 1888 and the copper clyinder held 40 gallons of water in which sodium bicarbonate was dissolved to which was added sulphuric acid.

A kit is available 1563K.
Also accessories Copper Cylinder,
Set Brass Valves, Copper Wire, Nylon Cord and Transfers for above plan.