90 



SCIENTIFIC NEV/S. 



[June 1st, i£ 



work. If, on the other hand, the tube ci be connected with 

 any apparatus requiring exhaustion, the suction produced 

 at d will effect this purpose. It is said by La Nature that 

 the first design for this apparatus was made in 1872 by M. 



Fig. I. 



Lane (a pupil of M. Sainte-Claire Deville), and that he first 

 used it at the Sorbonne laboratory. 



It is, however, somewhat singular that an apparatus 

 similar in principle was long ago devised by Sir Charles 

 Cameron, the Medical Officer of Health and Public Analyst 

 for Dublin, ex-President of the Royal College of Surgeons 

 in that city. In fact, it has been in use since 187 1 in the 



Fig. 2. 



college laboratory, and, as we have seen it in operation 

 there and know it to be simple and efficient, we think it is 

 due to its inventor that it should be mentioned ; at the 

 same time, some of our readers may be glad to know of 

 it. The apparatus referred to is shown in Fig. 3, in which 



a is the tap for admission of water from the street main ; b 

 is an upper and c a lower cone, by means of which air is 

 sucked in through d, and forced through the tube/ into the 

 vessel A, when the water is turned on ; ^ is a syphon for 

 drawing off water from A, and h is an air-vent to prevent 

 the flow of water being checked by an accumulation of air. 

 When the cock e is opened, there is an escape of air at 



T 



Fig. 3. 



pressure, which is used for blow-pipe and other work, and 

 when required the tube d is connected with any apparatus 

 requiring exhaustion, as in Fig. 2. 



It will thus be seen that there is a remarkable resem- 

 blance in the working of the two apparatus, and that both 

 of them are designed to give identical results. 



The Accident at Crarae Quarry.— A bluebook has been 

 published, containing the report of Colonel A. Ford, Her 

 Majesty's Inspector of Explosives, on the explosion at Crarae 

 Quarry, Loch Fyne, on September 25th last year. It will be 

 remembered that a large party went on a steamer to see the 

 effect of some blasting operations in the quarry, and that 

 after the explosion they visited the spot. Many of them were 

 seized with faintness ; si.x were dead when rescued, one died 

 afterwards, and five others were conveyed to the infirmary at 

 Greenock, where they recovered. Colonel Ford gives in minute 

 detail the gases which must have escaped after the explosion of 

 13,000 lbs. of gunpowder, and describes the symptoms which 

 were developed in the injured persons. Probably, Colonel Ford 

 says, the mischief was done by the carbonic oxide — of which 

 468 lbs. were generated by the explosion, an amount which, at 

 the ordinary temperature and pressure, would occupy a space of 

 6,333 cubic feet. This would be sufficient to vitiate one hun- 

 dred times as many cubic feet of air, but in the presence of 

 carbonic anhydride — of which 3,575 lbs. were generated — it 

 would render 1,266,600 cubic feet fatal to human life. 



