366 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



that has excited so much objection to steam carriaj^es and rail cars, on the 

 assumed but not proven ground that they are less safe than horses. If 

 steam cars should displace all the horses now working- the passenger 

 traffic, all the accidents from the fright of cart horses, fancy horses, and 

 all other horses remaining in use, would be less than the accidents now 

 occurring from the fright of the horses that would be displaced by the 

 -steam cars. 



The other danger apprehended is the explosion of boilers. Col. Maceroni, 

 who built a steam carriage that ran very efficiently, in reply to an inquiry 

 as to the safety of his boiler, placed himself and his two children on the 

 carriage, fastened down the safet}' valve, drove the fire, and actually 

 bursted the boiler, and that without disturbing anything but the ruptured 

 part. Jacob Perkins frequently had his cast iron tubes burst under 750 

 pounds pressure, but never had a brick thrown from the furnace, and it is 

 a well established fact that high pressure steam does not scald. I have 

 had water from a high pressure boiler blown into my face without scald- 

 ing. The principle of subdivision of a boiler into small compartments may 

 be carried so far as to secure absolute safety. 



Some locomotive boilers on the New York and Erie railroad have 

 barrels forty-eight inches in diameter, made of quarter inch plates, single 

 riveted, and have been run whole trips with 200 pounds pressure. I design 

 boilers for steam carriages twenty-four inches in diameter, of quarter inch 

 plates, double riveted. The double riveted joint was found by Fairbairn's 

 trials to be stronger than the single riveted, in the proportion of 70 to 56, 

 or 10 to 8; hence, my boilers are two and a half times as strong as these 

 locomotive boilers, and will bear 500 pounds as safely as they will bear 

 200. But I don't propose to work them above 150 pounds. With this 

 excess of strength they are no more liable to burst than a building is to 

 fall. 



I have tried the subdivided tubular boilers, but have not succeeded in 

 making them produce steam well, and I find that I can vaporize more 

 water with a comnKui boiler of 160 feet of surface, than Ogle & Sumner's 

 did with 250 feet in a boiler of the subdivided kind. It is, therefoi-e, expe- 

 dient for me to use abundance of metal in the shell, rather than attempt to 

 improve the boilers that are naturally safer, while I have not adequate 

 capital. When I have sufficient capital I intend to experiment upon them, 

 and to neglect no reasonable means of safety. Two engineers of acknow- 

 ledged talent have patented steam generators that are unquestionably safe, 

 and will, I believe, make steam fast. They have promised the exclusive 

 right of them for common road and street locomotion to a company, if I can 

 form one with adequate capital. 



Fifth, the cost. The average cost per mile, of locomotives on the Illinois 

 Central railroad, for seven years, was sixteen and two-third cents; on the 

 New York Central it is from twenty to twenty-one cents, wood being the fuel; 

 on the Baltimore and Ohio fifteen cents, with coal. The small tank engines 

 built by Danforth, Cooke & Co., worl^for six cents per mile. The cost per 

 car per mile, for haulage, is less than two cents, at a speed of over twenty 

 miles per hour. The contract price of drawing cars by horses at less than 

 six miles per hour, on the Hudson liiyer railway, has been twenty-five 



