178 Proceedings of the 



January 29 th. 



This evening Mr. Fordham gave an account of his proposed 

 method of transferring the power of water-mills, stationary steam- 

 engines, or other cheap first movers, to locomotive engines and 

 carriages, intended to travel on common turnpike roads. His pro- 

 posal is to compress air by the power of these motors, and then 

 employ its elastic power in propelling the carriages. The following 

 is a brief prospectus of his plan. 



The air will be condensed by the power of steam-engines, water- 

 mills, or any other cheap prime mover. The air, when condensed, 

 will be contained in strong but light iron vessels, called recipients ; 

 a certain number of these recipients, fixed in a frame, and opening 

 into one common main pipe or tube, will be called a reservoir. 

 Each reservoir will contain a quantity of condensed air sufficient to 

 propel a carriage of a certain weight, one stage of eight or ten 

 miles. The carriage in its appearance, or external form, will 

 resemble a steam-boat in miniature. The wheels will support, and 

 also give motion to the vehicle : the reservoir will be suspended 

 beneath the axle ; and the bottom of the frame should not be more 

 than nine inches from the ground. The machinery will consist of 

 two or more cylinders, with pistons, connecting rods, and the appa- 

 ratus for communicating motion, which is commonly used in high 

 pressure steam-engines. The valves must be made to close at any 

 part of the stroke, for it is necessary to let the air expand in the 

 cylinders, and it will be advantageous also to let the air pass from 

 one cylinder to the other ; working in each or all expansively ; and 

 permitting it to escape from the last into the external atmosphere. 

 With these conditions in view, a carriage for conveying the mail 

 may be made of the following weight : 



42 

 The velocity or rate of travelling of such a carriage as this, may be 

 fourteen miles per hour ; the expenditure of air on ten miles will 

 not amount to 2000 cubic feet ; the reservoir will contain upwards 

 of 3000 cubic feet. 



