222 ANNUAL OF SCIENTIFIC DISCOVERY. 



ice to be 75 pounds per square inch ; then the mechanical work, 

 which acting within the mass is necessary to put the glacier in 

 motion, as it actually moves, is 61| units of work per square inch 

 of the surface of the glacier per day." (See Proceedings of the 

 Royal Society, January, 1869,^9. 207.) 



"Now this quantity of work would be supplied by .0635 heat-unit 

 entering the ice per square inch of the surface per day, and diffus- 

 ing itself through it, each heat-unit being the heat necessary to 

 raise 1 pound water by 1 F. Far more than this heat probably 

 passes the surface, and enters into the ice of a glacier on days 

 such as that when the motion was observed, which serves as the 

 basis of these calculations." 



This theory presupposes that the ice in the interior of the gla- 

 cier is a solid. In reply to the objection which might be brought 

 forward, that according to the experiments of Agassiz the tem- 

 perature of the interior of the glacier is nearly constant at 32 F., 

 Canon Moseley says : 



"Nothing can be concluded from these experiments, because 

 the thermometers were not frozen into the ice of the glacier, or the 

 mouths of the borings so effectually stopped as to prevent the 

 access of air or the percolation of water from the disintegrated ice 

 of the surface. The included thermometer could but remain at 

 zero (Centigrade), however low might be the temperature of the 

 surrounding ice, for the water of the air continually freezing on 

 the sides of the boring would raise the temperature around the 

 bulb by the latent heat set free in freezing to C. A thermom- 

 eter is, in short, incapable of taking the temperature of ice, 

 unless the ice be dry. Proc. Eoyal Institution, 1870. 



DISCOVERY OF THE DIAMOND IN BOHEMIA. 



In a letter to H. Sainte-Claire Deville, M. Schafaritz, of Prague, 

 announces the discovery of the diamond at Dlaschkowitz, about 

 CO kilometers north-west of Prague, in a bed of gravel situated 

 in the Cretaceous formation. The gravel, which consists, in part, 

 of debris of the basalt of the Mittelgebirge, together with gneiss 

 and serpentine, contains a large proportion of quartzose sand, rich 

 in grains and worn crystals of various precious stones, among 

 which the most important are pyropes (Bohemian garnets con- 

 taining oxide of chromium) and zircons. There also occur red 

 and black spinel, chrysolite, kyauite, pyroxene, amphibole, etc. 

 The single specimen of diamond found is of irregular, cubical 

 form, from 2.5 to 4 m. m. in diameter, and weighs 57 rngrm. 



M. Schafaritz says : " This discovery of the diamond at Dlasch- 

 kowitz appears to me important, not only because it is the first 

 authentic case of its occurring in Europe (excepting in the Ural 

 mountains), but also in a geological point of view. Up to the 

 present time the diamond has been found only in formations which 

 everywhere are almost identical and characterized both by their 

 geological horizon between the early sedimentary and the azoic 

 rocks, and for the association of the diamond with gold and 

 platinum. Here the conditions are entirely different ; no gold or 



