602 



NATURE 



[October i8, 1900 



gaseous mixture become heavier, but it becomes cooler 

 by the rapid volatilisation of the petroleum, and this 

 cooling action is greater the more rapid the passage of 

 air through the receptacle. As the absorbents may be 

 regarded as solids, there is no danger either from the 

 presence of loose petroleum or of explosion. 



These carburetters (or, as they are termed, aero-gas 

 fountains), in the form best adapted for lighting and 

 heating purposes, consist of a reservoir of ordinary tin, 

 with an air admission regulator at the top and a bent 

 -draw-off pipe at the bottom, the pipe being so designed 

 as to syphon out the gas and prevent the possible over- 

 iflow of any loose petroleum that might be left on the 

 '•bottom from an overcharge. Fig. i is a vertical section 

 •of such a carburetter. The carburetter is divided 



Fig. 4. Fig 5. 



horizontally by two perforated shelves, the object of 

 which is to produce a longer travel of the gas, and to 

 •distribute it through the perforations. Fig. 2 is a plan 

 of the top of this fountain, while Fig. 3 is a drawing of 

 one of the perforated shelves. The absorbent is a 

 species of wood pulp which is entirely unaffected by 

 the petroleum, and acts merely as a means of holding it 

 in suspension. 



With the carburetter as applied to table and other 

 lamps, the burners used are argands, with steatite centre 

 and very wide gas ways. The light is of high illuminating 

 power and of remarkable purity. For street lighting the 

 ■carburetter forms part of the lamp, which has a hinged 

 top, so that when the carburetter is exhausted it can be 



lifted out and a fresh one put in its place. For ships' 

 lights, as well as in railway and other signal lights, the 

 system offers peculiar advantages. With respect to 

 heating, all classes of stoves can be adapted for this 

 system. 



There is one other most important branch of lighting 

 for which the carburetter is designed, namely, light- 

 houses, beacons and buoys. The advantages of gas as 

 an illuminant were early apparent to lighthouse 

 authorities, and in the Government inquiry into the 

 relative advantages of paraffin, gas and electricity as 

 sources of light for lighthouse illumination, the superiority 

 of gas was clearly pointed out, but owing to the necessity 

 of elaborate plant needing to be installed in the vicinity 

 of each lighthouse to be lit by gas, it was pointed out 

 that, despite its intrinsic advantages, it 

 could not be recommended on account 

 of the expense and difficulty entailed in 

 the production. Since those days, how- 

 ever, the Pintsch system of vaporising 

 oil for gas, despite its costliness both as 

 regards the gas produced and the plant 

 required, has been largely made use of 

 by the lighthouse services both at home 

 and abroad. The simple automatic car- 

 buretters that have just been described 

 will, it is clear, place within reach of the 

 lighthouse authorities the possibility of 

 making use of gas-light in place of the 

 paraffin lamps now in common use. Figs. 

 4 and 5 show section and elevation of a 

 third order dioptric apparatus in which 

 the carburetters are placed above. In 

 place of the oil tanks required for the 

 storing of the paraffin, the tin carbu- 

 retters can be served out to the various 

 stations ready charged, and these can be 

 returned when exhausted and fresh ones 

 supplied. As the absorbent takes up 

 about three-quarters of its own volume 

 of liquid, it is seen that the room required 

 for storing the fountains or carburetters 

 is little more than that needed for the 

 present paraffin supply. As the flame 

 given from this aero-gas is steady and 

 constant, the trouble of maintainmg the 

 old paraffin burners of many wicks, so as 

 to give a constant light, is obviated. By 

 doing away with the constant level and 

 pressure arrangements now in vogue, a 

 considerable economy will be effected in 

 light-house apparatus, while at the same 

 time the risk will be lessened of a failure 

 of some part of the mechanism. 



In their application to engines for 

 motor-cars, launches, &c., these fountains 

 have a very wide field of usefulness, in 

 which they offer advantages that cannot 

 be secured without them. 



J. A. PURVES. 



NOTES. 



We regret to see the announcement of the death of Sir 

 Henry Wentworth Dyke Acland, K.C.B., F.R.S., late Regius 

 professor of medicine in the University of Oxford. The funeral 

 will take place to-morrow (Friday) at Holywell Cemetery, 

 Oxford. 



Prof. T, G. Bonney, F.R.S., has resigned the chair of 

 geology which he has worthily occupied at University College, 

 London, for a period of twenty-three years. The chair will 

 become vacant at Christmas. 



NO. 



616, VOL. 62] 



