Chemistry and Physics. 145 
evolved could be measured in a calorimeter. e values 
obtained were considerably greater than those calculated from 
the well-known heat of combination of sulphuric acid an c 
in 
sulphate, and the results were interesting chiefly as controlling 
e placed on this new class of chemical constants. Inves- 
tigations similar to this were undertaken by other students, but 
without equal success, and the results are reserved until sufficient 
data have been obtained to warrant positive conclusions. ; 
. S. H. Kyieurt, of the graduating class, re-determined the 
boiling point of sulphur by the method contrived by the writer, 
i tt 
two-tenths of a degree, a value which is several degrees higher 
than that recently given by Professor Crafts. But although Mr. 
Knight’s results agree very closely with that previously 
the sulphur, or by the effect of the vessel used. The vessel, mad 
of cast iron, was lined with a porcelain-like glaze, and directly 
heated with a gas flame. ‘ 
Mr. Otiver W. Hunrineron has determined the crystallin 
form of chlordibromacrylic acid, C,ClBr,0,H,, obtained as above 
by Dr. Mabery. The crystals are oblique prisms and have a 
of the crystal were calculated from the fundamental angles 010 on 
100=66° 23’, 100 on 001=116° 17’, 010 on 001=116° 20’, 100 
on 101=63° 50’, 100 on 110=47° 5’. The calculation gives 
@:b:¢: = 0°79807: 1: 0°72072 Pier 
*eony 104° 43’; yonz 71°6'; eony 71 10. 
Besides the planes above enumerated the following were also de- 
termined : 
430; 034; 304? 740; 470; 474; 047? 
Mr, Huntington also has had in preparation a collection of 
chemical tables, and of these a set of logarithms to five places of 
decimals, arranged on an ingenious plan to facilitate rapid refer- 
_ &nce, have been published. | i 
2. Electricity due to eva oration.—In order to test the point 
whether the vapor arising from electrified surfaces of fluids 1s 
Jour. Scr. —Turep Series, Vou, XXVI, No. 152.—Aveust, 1883. 
