Proceedings of the Polytechnic Association. 985 



The Cliairman remarked that this was entirely an iVmerican inven- 

 tion. The principle is fully explained in Ewbank's hydraulics. Mr, 

 Ewbank states that a tube made like the atomizer would draw up 

 mercury in it seventeen inches, or about three-fifths of the column 

 measuring tlie weight of the atraosDhere. It was on this principle 

 that the Gifford injector was constructed. Some twenty years ago 

 Mr. Ewbank applied, this idea hi this country to cause a draft in 

 chimneys. 



Dr. J. J. EdAvards said that one of the difficulties in dental anaes- 

 thesia is that the gas cannot be given without assistants, and then it 

 tries the patience of the operator before the teeth are taken out. Tlie 

 atomizing process is a great improvement on the anjesthetic method, 

 and the plan here shown M'hicli dispenses witli assistants is valuable. 

 It is an economical machine; one man can use it witliout any difficulty. 



Dr. P. H. Yandervv-eyde said the atomizing blowpipe, made on the 

 principle of the Giftard injector, was used by him as a pump for steam 

 fire engines, but was found not to have the power of the pump, and 

 so was' abandoned. This principle is used quite extensively; the 

 latest application is to " age" whisky with it. "VVe all have doubtless 

 lieard of the recent case of a wine cellar being struck by lightning and 

 scattering the wine in all directions, which after being gathered up was 

 found to be much improved, but the improvement was nothing more 

 than bringing the air to the wine. The loss by evaporation of the wine 

 by aerating it, is said to be trifling. A patent for improving wine by 

 electricity, has been granted, but it is not done like nature as a gal- 

 vanic batter}'- is used. He employed a pump on this plan of the blow- 

 pipe to water flowers. 



The Chairman remarked that the Gilford injector carries the heat 

 of the steam used back into the boiler through the water injected, 

 and in this case is not a wasteful application of steam. For other 

 purposes it might do to use the waste steam to be blown ofi" into the* 

 air ; in this way only it is economical. 



Prp:ssuke and Vacuum Gauge. 

 Mr. W. IT. Chase exhibited the American Eagle Steam Pressure 

 and Yacuum Gauge. This gauge, he said, in the simplicit}' of its 

 construction and strict reliability, is placed next to the syphon or cis- 

 tern mercury gauges, which are known as the only gauges entirely 

 reliable in their indications. This gauge is a mercurial steam gauge, 

 which can be easily adjusted. The diaphragm is nickle plated, which 



