Professor Clark's Gas Burner. 



385 



I 



cular projection//". There are two stop-cocks. The 

 horizontal one g is for admitting the supply of gas, 

 which passes up the fixed tubepp into the sliding tube 

 m m. Between the outer fixed tube 1 1 and the inner 

 fixed tube p p, water is contained to serve as a lute to 

 confine the gas. The sliding tube is kept at whatever 

 height it may be placed, by means of a spring inserted 

 in a stuffing-box formed by the screws 5 above ff. 

 The spring is represented apart, r. It is formed out 

 of a short bit of another metallic tube of such bore as 

 only to permit the tube mm to slide through it easily. 

 Four holes in the circle of the wider tube r are bored 

 at equal distances, and a vertical slit is cut by a saw 

 from each hole through to the bottom of the tube. 

 After being thus cut, the cut parts are squeezed to- 

 gether by the hand, and the tube r being put over 

 the tube m and confined in the stuffing-box at s, forms 

 a convenient spring for keeping the sliding tube m at 

 whatever height it may be placed. The stop-cock w 

 is to let out any water that may by accident get into 

 the tube pp. The tube mm should not be less than 

 half an inch in diameter. The burner b, which is 

 copied after one inProfessor Graham's laboratory, Uni- 

 versity College, burns after the manner of a rose- 

 burner, but it is in the form of a ring, instead of 

 being solid. It may be called a ring-burner. It per- 

 mits a much more free access of air, especially when 

 the flame is placed very close to a vessel. This burner 

 also supplies gas very advantageously for mixture with 

 air in a cylinder, at the top of which the mixture 

 burns over wire gauze. The sliding tube relieves the \l |J 8 



operator from all cumbrous supports to his burner, or 

 from the necessity of having moveable supports to 

 the vessels to be heated. A ring supported by three 

 legs, the whole made of tinned iron, affords a cheap, 

 stable and convenient support to vessels, although of 

 considerable weight." 



" On some Salts of Cadmium," by Henry Croft, 

 Esq. This paper is inserted in the present Number 

 of the Philosophical Magazine, p. 355. 



" An Examination of two specimens of South Sea Guano, im- 

 ported for agricultural use," by George Fownes, Esq. 



No 1. — Presented the aspect of a pale-brown soft powder, with 

 a few lumps, having in their inside whitish specks ; its odour was 

 exceedingly offensive. 



Treated with hot water and filtered, it gave a yellow, feebly alka- 

 line solution, not rendered turbid to any extent by the addition of 

 acid, which contained much ammoniacal salt, some sulphate and 

 chloride, a very large quantity of oxalate, and both potash and soda, 

 the latter most abundant. 



