1855.] 



PROCEEDINGS OF THE CANADIAN INSTITUTE. 



133 



Collins' steamers not excepted, is the want of room necessary 

 for a due mixture of the gases, and a full developement of the 

 blaze. 



Large quantities of fuel in a naiTow and low furnace cannot 

 be consumed without waste. In order to become fully excited 

 and most positive in its action, the blaze of a fire must be at 

 liberty to extend and elongate in the direction of the draught 

 to a distance corresponding to its bulk, and without meeting 

 absorbing obstructions. For illustration I again refer to heating 

 and puddling furnaces. This fact can be readily ascertained in 

 an experimental furnace with adjustable roof. The brightest 

 fire will burn under the highest roof, while the depressing action 

 of a low roof will damp it, and reduce the temperature of the 

 furnace. 



Economy of space is an important consideration in the 

 planning of a marine boiler ; but this may be carried so far as 

 to seriously interfere with the grand object of the boiler. In 

 an efficient boiler the extension of the furnace should form an 

 empty area, which serves as a receptacle for the caloric stream, 

 where the gases become thoroughly mixed and fully ignited 

 before their caloric Ls expended upon the boiler surface ; and 

 for the purpose of allowing ample time to the heat to be ab- 

 sorbed by the tubes, the above space, together with the tube area, 

 should be as large as possible. The arrangement must be so 

 that the draught between the furnace and the chimney should 

 be very slow, so that all the caloric, or nearly all, may be ab- 

 sorbed before the unconsumed gases are allowed to escape. 



The boilers of the Arctic have 33 feet of heating surface for 

 one foot of grate surface : this allowance is scarcely enough for 

 hard coal — 10 to 1 will not prove an excess. But this propor- 

 tion depends, in a great measure, upon the velocity of the 

 draught through the area which contains the tube or heating 

 surface. The larger this space, or the longer its extent, the 

 slower the motion of the gases will be ; or the more extended 

 their travel, consequently the longer they will remain in con- 

 tact with the tubes. It is a very general defect in marine boil- 

 ers, that the draught from the furnace to the chimney through 

 the tube area, or through the flues, is nearly uniform, and too 

 rapid. The "hanging- sheets" in the boilers of the Collins' 

 steamers were designed to arrest this rapid flow, but they are 

 not sufiicient. The fact is, that the common plan of flue or 

 tube boilers does not admit of a thorough application of the im- 

 portant principle in question; hence the necessity of a radical 

 change. 



Other questions of importance have to be considered in the 

 planning of a marine boiler. Strength, facility of construction 

 aud repairs, provisions against unequal contractions and expan- 

 sion, against incrustation, facility of blowing out and of clean- 

 ing, safety against exposure of heating surface when the ship is 

 rolling or careening — all these are important points, but more 

 or less understood. By the above remarks I have only at- 

 tempted to direct attention to such points as are not generally 

 understood, and conscquentlj- neglected. In a new plan of 

 boilers which I have invented, all the essential conditions of 

 perfect combustion, radiation, and absorption are fulfilled, and 

 are calculated to produce much higher results than have been 

 obtained heretofore. 



In conclusion, I will j'ct remark that the subject of artificial 

 draught is, in a great measure, an open question yet. The com- 

 mon fan-blast will answer very well under certain conditions ; 

 but"iii marine boilers, I am sati.sfiod, exhaustion V)y pnijier nio- 



chanical means will work better. The control of large and con- 

 nected fires can be better maintained ly exhaustion than by 

 blast, and also more economically. — Scientific American. 



INCORPORATED BY ROYAL CHARTER. 



CANADIAN INSTITUTE. 



SESSION 18-54-55. 



First Ordinary Meeting— Saturday, Decemlier iid, 1S54. 



The names of the foUoiving candidates for membership -were read : 



Charles Fitzgibbon Toronto. 



Richard Fomeri " 



Arthur A. Farmer 'Woodstock. 



Lawrence Laurason London. 



John T. Newton, JI.D Sault Ste. Marie. 



Hector Cameron Toronto. 



Rev. W. Leach, LL.D Montreal. 



W. Kingston, M.D " 



Alex. Rennie " 



Andrew Dickson Packenham. 



Hewith Bernard Barric. 



A communication from the Council was read, being the " Report of 

 the Special Committee appointed to consider Major Lachlan's sugges- 

 tions with respect to the establishment of a series of Meteorological 

 and other Observations throughout British North America." 



REPORT. 



The Committee appointed to consider Major Lachlan's suggestions 

 with respect to the establishment of a series of simultaneous Meteoro- 

 logical observations throughout the British American Provinces, beg 

 leave to report, that after giving due consideration to the plan suggested 

 by Major Lachlan, they have thought it advisable, before recommend- 

 ing any special steps to be taken, that correct information should bo 

 procured with reference to the working of a similar system in the 

 United States, which has now been in operation for some years. Tbo 

 Committee have requested one of their members to communicate with 

 Professor Ilenry, the Secretary of the Smithsonian Institution, as well 

 as with other gentlemen in the United States and Canada, whose views 

 on this subject the Committee consider it essential to obtain. Not 

 having yet received the required information, the Committee are un- 

 prepared to recommend to the Council any definite course of action. 



