640 Chronicles of Science. [Oct., 



whilst the fire-grate must be so arranged as to avoid the disadvan- 

 tages usually attendant on the use of slack, such as the loss of a 

 quantity of fuel by falling, unconsumed, through the bars, or the 

 obstruction of a proper draught by cakeing into blocks over them. 

 Fire-doors of this description are made by Messrs. Newton and 

 Newton, at Liverpool, and appear to possess great advantages, not 

 only in enabling slack to be burned where large coal would other- 

 wise be necessary, but by a proper regulation of the air admitted to 

 furnaces to which they are fitted, more perfect combustion is 

 ensured, resulting, consequently, in the almost total prevention of 

 smoke. 



We cannot close this subject without a brief notice of Mr. 

 Thomas Kussell Crampton's process of burning fuel in the form of a 

 powder. Many previous experiments have been made both in Eng- 

 land and America to effect a similar object, but they have failed to 

 achieve that amount of success which Mr. Crampton appears to have 

 arrived at. Mr. Cram23ton's process, described in few words, consists 

 of an arrangement by which a portion of finely-powdered coal is 

 blown into a furnace, where at first a small fire has been lighted. 

 This immediately bursts into flame, and by properly adjusting the 

 proportions of air and coal-powder, a flame is then regularly kept 

 up, giving out an intense heat, and leaving httle or no residue in 

 the shape of clinkers or ash. Want of space prevents further 

 allusion to this subject now, but we shall return to it again upon 

 some future occasion. 



Meetings op Scientific Societies. 



Institution of Civil Engineers. — The President's annual con- 

 versazione took place on Tuesday, the 25th May last, at which 

 there were present an unprecedented number of mitors and mem- 

 bers. The meetings of the Institution have now been suspended 

 until the autumn. 



Institution of Mechanical Engineers. — The annual meeting of 

 this Society was held at Newcastle on 3rd August last, and follow- 

 ing days, under the presidency of Su- William Armstrong, when the 

 following papers were read ; — " On the Hydraulic Swing Bridge 

 over the Ousc," by the President ; " Mechanical Ventilation of 

 Mines," by Mr. William Cochrane, of Elswick ; " Mechanical 

 Firing of Steam Boilers," by Mr. John Daglish, of Seaham ; " Hy- 

 drauhc Machinery for AVarchousing Grain," by Mr. Percy G. B. 

 Westmacot, of Elswick ; and on " The Navigation of Canals," by 

 Mr. Max Eyth, of Leeds. The President, in his address, which 

 was given before a crowded audience on the evening of the first 

 day's meeting, after alluding to the present year being the cente- 



