In a paper read before the German Physical Society, Mr. H. Starke describes experiments on cathode rays, which confirm the idea that the apparent mass of the flying corpuscles is purely electrical.

An Italian has invented a saturation hygrometer which may be used for determining the tension of aqueous vapor in the air in small spaces, such as instrument cases; a portion of the air to be examined is withdrawn and satured with aqueous vapor, and the increase in pressure thus caused is noted. Knowing the saturation vapor pressure, it is possible to deduce the aqueous vapor of the experimental air. The apparatus consists of a bronze receiver fitted with a thermometer; into the receiver passes a glass tube drawn out at the lower end, and connected at the upper end with a syringe which serves to force in drops of water. The receiver may be put in communication with the exterior air, and carries at the side a graduated tube of 3.2mm. diameter, containing a column of petroleum 2.5cm. long.

The turning lathe is the best premium ever offered in this country.

A remarkable phenomenon is reported at St. Petersburg, from the rural commune of Schava, in the Government of Tsarey. Inexplicable noises were heard for several days issuing from the earth. The sounds varied from something like the booming of cannon to the screeching of steam whistles, and seemed to come from a forest skirting the commune. In this forest, where the terrified peasanty gathered in expectation of some great calamity, the earth was seen to heave incessantly. Gradually huge cracks appeared, the earth seemed to sink, water rose, and there came to view a new lake, of considerable extent, which is now being examined by geologists.

The latest record broken is in the ballooning line, and a message from Berne informs us that a balloon has reached the enormous attitude of almost 11 1/4 miles. This is an improvement on the first notable ascent, 120 years ago, when 1, 500 ft. was the height attained. This Swiss balloon, of course, carried no human cargo, but only self-registering instruments. These showed that the greatest cold experienced was 58° below zero. Men have managed to ascend to an altitude of seven miles, but their condition was fraught with great danger. Perhaps in the future some contrivance, in the shape of a closed car, may be invented, which will permit of much loftier ascents ; but there seems hardly sufficient inducement to warrant the risk.

Steam Generation, says Cassier's Magazine, is the result of several processes which are carried out with a boiler or generator of suitable design. These processes are (1) combustion, which means the combination of the oxygen of the air with the carbon, hydro- carbons, and hydrogen of coal or other fuel at a suitable temperature; (2) transmission of heat; (3) change of the physical state of the water in the boiler, in which is involved the phenomenon of latent heat.

Prof. Himstedt, of Freiburg, claims to have made an interesting discovery respecting radium, which seems to show that its existence is far more widespread than heretofore supposed, His experiments are asserted to prove that all products of water and petroleum sources yield a heavy specific gas, closely resembling, and probably identical with the emanation of radium.