722 Transactions of the American Institute. 



head, aside, which brings each tube over the opening between the 

 two tubes below it, in which case the return bends that connect the 

 tubes together are put on diagonally, as shown in lithographs. 



In each head are two openings, a, a. Through these openings 

 and the elbow bends, i), D, each tube is connected with the tubes 

 al)ove and below it. These elbow bends are held in place by- 

 clamps and stud bolts, E, locked into the heads. The ends of the 

 bends are seated on rubber washers, b, b, vulcanized to stand high 

 temperatures, thus making the joints steam and water tight. The 

 lower horizontal row of tubes is connected in the same manner at 

 the lower rear corner to the water cross-pipe, E, into which the 

 feed water is forced, and the upper horizontal row of tubes is con- 

 nected at the steam cross-pipe, G, at the upper front corner, from 

 which the steam is taken to the engine thi'ough the steam-pipe, H. 

 The fuel is burned on the grate bars, Ji, in the usual manner, and 

 the flames and heat pass upward through the boiler, among the 

 tubes, over the iron bridge, U (which extends up from the fire brick 

 bridge wall, 0), and pass out of the boiler through the flue. Where 

 it is more convenient, the draft may be taken out at the top and 

 rear of the boiler. 



The corner stays, side stay bars, door frames and bearing beams 

 hold the lower portion of the walls firmly in position, and the wall 

 panels, cross and lengthwise stay rods keep the side walls and top 

 in place. X, fire door; M, ash-pit. The water line is at IF, and 

 the large stand pipe, /, with its water connecting pipe, P, and 

 steam connecting pipe at the top, with the glass water gauge, J, 

 and try-cocks show the level of water in the boiler. S, floor 

 line; V, damper in flue. Adjourned. 



October 24, 1867. 

 Prof. S. D. Tillman in the chair; J. Wtatt Reid, Secretary. 

 The Chairman presented the following summary of scientific 

 news: 



DEODORIZATION OF KEROSENE AND COAL OILS. 



According to Wagner, the peculiar odor of these oils is removed 

 by treating them with a solution of oxide of lead in caustic soda. 



TIIE COLOR OF MARS. 



Mr. Huggins, F. R S., is of opinion that the color of the planet 

 Mars is not due to the peculiar absorption or other effects of Us 



