428 Chronicles of Science. [July, 



of snow or pounded ice, and one part of common salt ; after about 

 forty minutes the cylinder bursts with a loud report. It is essential 

 for the success of this experiment that the plug fits very perfectly, and 

 that the cylinder, after having been filled with water, be placed for 

 some time in ice. The wooden pail which contains the freezing 

 mixture should be roomy, and be covered with a stout towel to pre- 

 vent the spirting about of the contents at the time of the bursting. 



Some experiments on the freezing of wine have been tried by 

 A. Eousselle. The reason why freezing improves wines, under 

 certain conditions, is, according to this author, because by partial 

 freezing the proportion of all the fixed substances in the liquid 

 wine is increased ; and these are, moreover, thereby rendered more 

 fit for causing the combination of the acids with the alcohol, so as 

 to form those ethers to which wine owes its peculiarly distinct 

 flavour, aroma, and strength. 



Dr. Hann has tried to solve by observation the problem of the 

 decrease of the temperature of the air in relation to the elevation 

 above sea-level, by comparing the average of temperature as observed 

 at certain groups of stations situated under the same mean latitude 

 and longitude, and by taking into account local influences. Seven 

 of these groups are situated in the western portion of the Alps, at 

 from 230 to 3330 metres above sea-level; four in the northern 

 part of Switzerland, at from 500 to 1780 metres above sea-level ; 

 three in the Eauhe Alps (Wurtemburg), at from 310 to 810 metres 

 above sea-level ; four in the Erzgebirge (Central Germany), at from 

 180 to 850 metres above sea-level ; and four in the Harz (province 

 of Hanover and Brunswick), at from 70 to 1140 metres above sea- 

 level. The results obtained have proved that, in the instances 

 mentioned, the decrease of the temperature of the atmosphere near 

 the ground is really proportionate to the height of the locality above 

 sea-level. When the results of all the observations are duly con- 

 sidered, there is discovered a strongly marked annual periodicity, 

 and a very uniform decrease of temperature from below to above, 

 the average relation of the temperature reigning in December being, 

 to that of June, as 1 to 2. 



Dr. Yon Wartha has obtained solid disulphide of carbon by the 

 rapid evaporation of this liquid itself, in the same way as solid car- 

 bonic acid is formed. The solid sulphide melts at 9° F., and has the 

 appearance of small cauliflowers. 



Some time ago M. Lamy proposed a pyrometer based upon the 

 dissociation of carbonate of lime. He now proposes to apply ammo- 

 niacal chloride of calcium, which gives off ammonia at low tempera- 

 tures. The instrument is to be connected with a manometer, which 

 will record the temperature. The contrivance is to be especially 

 adapted to record the temperature at different depths under the 



