AMERICAN INSTITUTE. 487 



Ogle & Summers. Their water-spaces are less, the water-tubes being 2^ 

 and the flues 1|, and sometimes 1| inches, leaving but 5-16ths water- 

 spaces. There is very little water in the boiler, consequently the steam 

 caji be raised in about nine minutes, and when the fire flashes up, steam is 

 made rapidly; but when the fire deadens, the steam falls rapidly. I have 

 not seen these boilers do what is reported to be their best work ; the best 

 I have seen is about equal to that of Ogle & Summers' boiler. 



The boiler of the Storm fire-engine has 880 feet of surface ; that of the 

 Cary has 480. The Storm makes steam nearly as fast as the Gary. This 

 I attribute to the fact that the smoke crosses and recrosses the water-tubes, 

 and descends to the bottom, and thence ascends through the flues, giving 

 length of run and the advantage of the cross movement. The moving row 

 shown, gives an idea of the movement of the smoke. This design is mine, 

 except the old annular arran^-ement and the necks of the external row of 

 tubes, which are claimed in Mr. Larned's patent, I have another design 

 in which I dispense with the necks of the tubes, and turn the smoke out- 

 side, instead of inside, the bottom chamber. This arrangement places the 

 grate lower, and gives more room for combustion and more fire-bos sur- 

 face, and a longer travel for the smoke. I exhibit this plan merely for the 

 sake of asserting my claim to it, so that if it should prove to be valuable, 

 I may have the benefit of whatever there is new in it. I consider that if 

 made with water-spaces, sufiiciently wide, it will work tolerably well ; and 

 in cases where the cost of construction and repairs is a secondary consider- 

 ation, it may be of use. 



There is another kind of tubular boiler, which is worthy of mention, on 

 account of its safety — I mean that of Francis Macerone, which he used on 

 his steam carriage. It might be called a group of boilers, each being con- 

 nected with a water channel at bottom, and a steam drum at top j the 

 connections being as small as is permissible, so that if one bursts, the steam 

 from the others cannot rush out fast enough to do much harm. This boiler 

 was made up of eighty-one tubes, four inches diameter, and thirty-six 

 inches high, except the outer rows, which were forty -eight inches high, and 

 formed the walls of the fire-box; the smoke ascended between them. It 

 performed about as efiiciently as Ogle k Summers' The tubes were about 

 two-thirds filled with water. It is worthy of consideration whether these 

 tubes may not be so arranged that the smoke will more efi"ectually give its 

 heat to them ; and so that each tube may easily be disconnected from the 

 group in case of leakage. When steam is worked at a pressure of 500 lbs. 

 per inch, as I believe it will be, such a boiler may be the best. And it 

 does not appear that it need be very costly, either in construction or 

 repairs. 



A good boiler for locomotive purposes is much wanted. It is now 

 evident that steam can be applied to agriculture, common road locomotion,, 

 fire-engines, and other uses, that require portability. But, if a boiler is 

 costly, it will not pay ; if it is heavy, it will not pay ; if it consumes toO' 

 much fuel, it will not pay, We want a boiler that will vaporize not less- 



