Physics and Chemistry. 471 



transformed into oxycellulose, by paste printing. (2) immersion 

 in the vanadinrn bath for a definite time, rinsing and drying at 

 40°, (3) printing the strips sewed end to end, with bands of the 

 usual mixture of aniline black less the vanadium, (4) developing 

 the black in the oxidation chamber, and (5) classification. In 

 testing the process, hypovanaclic chloride was prepared from the 

 metavanadate of ammonium by the action of hydrochloric acid, 

 the reduction being effected by means of glycerin, the excess of 

 acid being removed by evaporation, and the solution diluted. 

 Six baths were thus prepared, containing pi-ogressively decreas- 

 ing quantities of vanadium from one tenth to one millionth of a 

 milligram per liter. The duration of the immersion was 8 

 hours at 15°. The specimens were prepai'ed by Osmond at 

 Creusot and classified by Witz at Rouen. The order of classifi- 

 cation was exactly that of the dilution, the strip treated in the 

 sixth bath which contained only one millionth of a milligram of 

 vanadium per liter being sharply distinguishable from that 

 treated with pure water. The authors give the effects produced 

 by the presence of foreign salts upon the result, and say that by 

 this test they have been able to detect the presence of vanadium 

 in the water supplied to Creusot and in the mineral water of 

 Saint Honore-les-Bains; but not in the body of a sheep of the re- 

 gion. — Bull. Soc. Chim., II, xliv, 309-315, March, 1886. g. r. b. 



5. On the Physical Properties of the C n H in+2 series of Hydro- 

 carbons from American Petroleum. — Bartoli and Stracciati 

 have examined the physical properties of twelve hydrocarbons of 

 the marsh gas series prepared by careful fractioning, from Penn- 

 sylvania petroleum. They find that as the molecular weight in- 

 creases, (1) the expansion-coefficients, both between 0° and 30° and 

 between 0° and the temperature of ebullition, decrease regularly; 



(2) the molecular volumes at the boiling point are not the same 

 as those which are calculated by Kopp's formula; an increase of 

 CH 2 not always corresponding to the same increase of molecular 

 volume, the differences being superior to errors of observation ;. 



(3) the capillary constants a 2 and a, measured at the ordinary 

 temperature, increase continuously, thus disagreeing with Wil- 

 helmy's result ; (4) the coefficients of friction at the temperature 

 of 22° to 23° increase rapidly and with regularity; (5) the index 

 of refraction measured for the line D, increases regularly ; (6) 

 these hydrocarbons have nearly the same specific heat; (7) they 

 do not conduct the electric current ; and (8) they have specific- 

 inductive capacities which follow Maxwell's law. The precise 

 values are given in a table — Ann. Chim. Phys., VI, vii, 375-383,. 

 March, 1886. g. f. b. 



6. On the Synthesis of Conine. — Ladenburg has studied the 

 reaction of paraldehyde upon a-picoline, with a view to the 

 synthesis of conine. The reaction requires a high temperature, 

 the yield even at 250° being small. The product was an oily 

 liquid difficultly soluble in water, having a boiling point at 190°- 

 195° and having an odor like conyrine. Analysis gave numbers 



