38 



UENSITIES OF OXYGEN AND IIYDROOKN 



st'eii reflected !>} a minor rarried by the beam. Of tlit- many merits wliieli tliis 

 lialaiiee possesses in the liii^hest iletrree vet attained, that one whieh made it desir- 

 al)le for my work was the great constancy of its indications. As was j»ro[)osed in 

 the pieliminary discussion with Kuepreclit, its sensitiveness has been reduced :iis far 

 as is 2)ermitted by the lange of the adjustment foi' this pur[u>se. 



MECHANISM I'Oi; WKKilllXC HV KKVEKS.M.. 



Fig. 16 gives a perspective view of the balance standing over the closet in 

 whicli ;d! objects to be weighed by reversal are containeil. The shafts and 



Fi'".. i6, — Balance standing on the closet which contains mechanism for transferring 

 objects from one pan of the balance to the other. 



hamlles In' which the balance is manipulated are seen a few centimetres above tlie 

 stone cover of the closet. The oscillations of the balance are ob.served by means 

 of tiie telescope, in which are .seen two images of a scale (not shown) placed over 

 the telescope, one reflected fi-om a mirror cai'ried on the beam of the l)alance, and 

 the other fnmi a fixed mirror placed just over the first. The latter image serves to 

 verify the stability of the scale and telescope. 



Just below the stone cover of the closet are seen the handles for manipulating 

 the rever-^al mechanism within the closet. The larger ciank rotates the .^^[lar.itiis 

 ill transferring an object from one [>an of the balance to the other ; the smaller 

 crank lifts and lowers the objects, and the milled head seen between the two cranks 

 moves latches for accurately centering and for keeiting unmoved the ajipaiatus. 

 A dial indicates the position of the reversal mechanism and of the several objects 

 with icfcifni-r t(i thi- |i;ins of the balance. 



