10 Professor Hare's improved Blo*wpipe. 



part of oil of turpentine, with seven of alcohol, be used, the 

 flame becomes very luminous. 



In order to equalize and regulate the efflux, I have contrived 

 a boiler, like a gazometer. It consists of two concentric cylin- 

 ders, opening upwards, leaving an interstice of about one 

 quarter of an inch between them; and a third cylinder, open- 

 ing downwards, which slides up and down in the interstice. 

 The interstice being filled with boiling water, and alcohol in- 

 troduced into the innermost cylinder, it soon boils and escapes 

 by the pipes. These pass through stuffing boxes in the bot- 

 tom of the cylinder. Hence their orifices, and of course the 

 flame, may be made to approach nearer to, or recede further 

 from, the boiler. 



The construction of this instrument, which I call the com- 

 pound blowpipe by alcohol, may be understood from the en- 

 graving (Plate I. Fig. 4.). 



The idea of making the flame of hydrogen gas, or alcoholic 

 vapour, more luminous by an adjnixture of oil of turpentine, 

 occurred to me in 1819; and I put the idea into practice in 

 the summer or succeeding winter of that year, when my pupils 

 witnessed the result. 



It seems, that Mr. Morey, by another catenation of ideas, 

 was led to a similar inference, employing, in an alcohol blow- 

 pipe, whiskey and turpentine. He endeavours so to regulate 

 the efflux of a single jet of the vapour of these fluids, as that 

 it may continue to burn, when once lighted. 



This process is too troublesome and precarious for ordinary 

 use. A mixture of alcohol and turpentine are burned with a 

 wick in a lamp, in the same way as oil, according to my plan. 

 It is of course perfectly practicable, and I shall be surprised if 

 it be not adopted in the western country, where alcohol may 

 be had very cheap, and oil must be comparatively dear. 



IV. Itemarls on the Trisectio7i of a Circular Arc. Ih^ Mr. 

 Paul Newton. 



To the Editors of the Philosophical Magazijie and Journal. 



Newark, May 4, 1 823. 

 CHOULD the following remarks, the result of much pa- 

 *^ tience, and of many attempts, on the trisection of an angle 

 or a circular arc, obtain a place in your Philosophical Maga- 

 zine and Journal, they may perhaps prove interesting to some 

 of your mathematical readers: That geniuses so exalted 

 as Newton, Barrow, Halley, in conjunction with an endless 

 list of other illustrious names of our own countrvmen. and of 



celebrated 



