Polytechnic Association Proceedings. 729 



cherry stonmg machine. 

 Mr. Gnielin, a German, has invented a machine for removing the 

 stones from cherries. It consists of a horizontal revolving wheel, 

 in the periphery of which are a series of cavities, each large enough 

 to hold one cherry. By the revolution of the wheel each cherry 

 is brought under a vertical rod, which by a sudden depression 

 forces out the stone and pushes it through a hole in the bottom of 

 the cavity, and then by means of a spring returns to its original 

 position, when it is ready for a descent upon the next cherry. The 

 fruit is fed into the wheel by means of a shoot. It is said the 

 machine will remove one hundred stones per minute. 



CAUSE OF THE SILKWORM DISEASE. 



Some years ago Baron Von Liebig expressed the opinion that 

 incomplete nutrition might be the cause of disease in the European 

 silkworm, and that the aliment offered them in the mulberry leaf 

 might not be sufficient for the formation of the cocoon. Recent 

 analysis of the mulberry leaves of France and Italy have confirmed 

 this opinion; it having been thus demonstrated that these leaves 

 contain a smaller amount of phosphates and nitrogenous substances 

 than those of the mulberry trees of China and Japan. 



TESTING GLYCERINE. 



The effect of glycerine {echarlilt) on tender and broken skin 

 should be mild, but physicians often hear complaints of its burning 

 and inflammatorj action, even when it has been largely diluted with 

 water. The effect of such a glycerine is now known to be due to 

 the presence of a certain amount of oxalates and formates, also 

 tracijs of ammonia. Litmus paper will remain unchanged in such 

 impure glycerine; but when the latter is mixed in a test-tube with 

 its equal bulk of sulphuric acid, a strong effervescence will take 

 place. It has also been ascertained that such glycerine was not 

 obtained by the process of distillation, but was only partially 

 purified by chemical action. 



LUCIMETER. 



This instrument, for measuring the quality of burning oils by 

 their illuminating power, invented by Mr. Deslauriers, consists of 

 two constant pressure lamps and a photometer, constructed on a 

 new principle. Its shape is triangular; it is made of sheet iron 

 painted black, and is divided into two equal compartments. The 

 latter are turned toward the lamps, while the observer stands ou 



