956 



SCIENCE. 



[N. S. Vol. XXI. No. .547. 



born and himself at the Physikalisch-Tech- 

 nische Eeichsanstalt during the years 1903-04, 

 with the object of bridging the gap in our 

 knowledge of the specific heat of gases between 

 200° and 1000°. Below 200° we have the ex- 

 periments of Kegnault and others, while be- 

 tween 1000° and 2000° we have the explosion 

 experiments. Regnault and his co-workers 

 found the specific heats, of the simple gases in- 

 dependent of temperature, while Mallard and 

 Le Chatelier have concluded that the specific 

 heats increase with temperature. The method 

 of mixtures at constant pressure was employed, 

 the gases being heated in an electrically heated 

 nickel tube filled with nickel filings, according 

 to the method of Wiedemann, and the heat 

 being taken up in the calorimeter by small 

 silver tubes filled with silver filings. The tem- 

 perature of the hot gases was measured by a 

 platinum/platinum-rhodium thermoelement at 

 the point where the gases entered the calori- 

 meter. After leaving the calorimeter the gases 

 were caught in a gasometer at atmospheric 

 pressure, the volume being measured by means 

 of the displaced water. The gases did not 

 come into direct contact with the water but 

 were caught in a rubber bag, so experiments 

 were possible with the more easily absorbed 

 gases. In Table I. the results for the simple 

 gases, and oxygen, nitrogen and air, are given. 

 These indicate an increase in the specific 



Tadle I. 



Between. 



N. 



0. 





Air. 



10-200° 



(0.2438)* 



(0.217 



5)* (0.2375)* 



20-440° 



0.2419 



0.2240 



0.2366 



20-0.30° 



0.2404 



0.2300 



0.2429 



20-800° 



0.2497 







0.2430 





Table II. 









□ 

 a 





a 



and 



"5 



91 



a 



Wiedemt 



Mallard ; 

 Le Chate 



Langei 



Ho', born 

 Austir 



0° 0.1870 



0.1952 



0.1880 



0.1980 



0.2028 



100° 0.214.5 



0.2169 



0.2140 



0.2100 



0.2161 



200° 0.2396 



0.2387 



0.2390 



0.2220 



0.2285 



400° 





0.2840 



0.2450 



0.2502 



000° 





0.3230 



0.2690 



0.2678 



800° 





0.3550 



0.2920 



0.2815 



* From Kegnault. 



heat of about three per cent, for air and nitro- 

 gen between 20°-440° and 20°-800°. 

 However, as the limit of accuracy is hardly 

 better than ± 1 per cent, the observed differ- 

 ence but little exceeds the possible errors of 

 observation. The results for carbon dioxide 

 are given in Table II. compared with those of 

 Regnault, Wiedemann, Mallard and Le Chate- 

 lier, and Langen. 



Mr. A. L. Day described ' An Interesting 

 Pseudosolid.' It was a fine foam made of 

 Plateau's solution or white of egg and sugar. 

 Cylinders cut from this showed elastic proper- 

 ties like a solid but through a wider range and 

 a fracture, photographs of which appeared like 

 marble fractures. Since the dimensions of 

 the cylinder under stress could not be measured 

 directly photographs were used; the results 

 were consistent to one half per cent. Poisson's 

 ratio came out nearly .50. He also detailed 

 the results of experiments on ' The Linear 

 Force of Growing Crystals.' Thus, an alum 

 cr5'stal raised a weight of 1 kg. per sq. cm. 

 through several tenths of a millimeter; the 

 growth takes place only at the lower edges and 

 the area of the supporting edge is too small 

 to measure with accuracy; the forces are of 

 the order of other molecular forces, and are 

 quite sufficient to produce and enlarge fissures 

 in the rocks. Both investigations have im- 

 portant bearings in geology. 



President Littlehales then read a biograph- 

 ical sketch of the late David Smith, chief 

 engineer in the navy (1834-1903) ; his most 

 notable services were in standardizing naval 

 equipment and in improving the ventilation 

 of ships. Charles K. Wead, 



Secretary. 



THE SCIENCE CLUB OF THE UNIVERSITY OF 

 WISCONSIN. 



The .eighth meeting of the club for the 

 year 1904-5 was held on Thursday, May 18, 

 at 7:30 p.m., in the physical lecture room, 

 Science Hall. 



The first paper of the evening, by Professor 

 J. L. Bartlett, dealt with the subject, ' The 

 Influence of the Madison Lakes on Local Air 

 Temperatures.' The speaker showed that 



