1899.] SCIENCE. 103
Tempel II. in May, Holmes and Tempel I. in June, and Giacobini, new, September 29.
Meteoric showers have been feeble. A few Perseids fell on each night between August 9 and 13. The Leonids disappointed all hope except for those persons who, like Professor Pickering, expect the maximum year to be 19012. An excited anticipation enabled some observers on November 15 to see a multitude of "stars like silver balls shooting about everywhere." The sky was bright in one case and misty in another, and the time was between three and four o'clock in the after- noon, when Leo was below the horizon.
Many new variables have been discovered, among which may be mentioned one in Andromeda, one in Vulpecula, and especially one of the Argol type, in Cygnus, with a period determined to be 4d. 13h. 45m. 2s.
The multiple stars, a Polaris and rj Pegasi, are shown to have variable velocities.
Spectroscopic examination indicates a heterogeneous composition of the Orion nebula.
Chemistry.
Professor Japp, in his address to the Chemical Section of the British Association in September, 1898, dealt largely with the subject of enan- tiomorphous bodies, and followed Pasteur in maintaining not only that optically active asymmetrical compounds are always the product of vital action, but that no selective agent that was not itself alive could separate the lsevo-rotatory and dextro-rotatory elements of a racemic compound. Such a picking out could be effected by micro-organisms, and might be wrought by human intelligence, but it could never be accomplished by ordinary chemical or physical forces unaided by a living operator ; and the chance synthesis of an optically active compound from inorganic materials was "absolutely inconceivable."
Mr. Herbert Spencer and Professor Pearson challenged the reality of these comprehensive assertions ; and further experiment and research were called for.
Meanwhile the question has not been allowed to rest. Messrs. Kipping, Pope, Rich and Peachy have made careful investigations, of which some mention may be made. A mixture of 25 grams of sodium ammonium dextro tart rate with 5 grams of the corresponding l»vo- tartrate in a 5 per cent, solution was found to have the specific rotation [a] D = + 16-60° instead of the calculated value [a] D = + 16-76°. The separating crystals were removed at intervals of several days, with the following result :—
Md Total material . . . 30 g. + 15-60° First fraction . . . 8 g. + 23-51°
Second fraction . . . 13 g. + 20-27° Residue 8 g. O
Sodium potassium dextrotartrate is isomorphous with the corre- sponding sodium ammonium leevotartrate, and forms a stable racemic compound with the isomeric lsevotartrate at ordinary temperatures.
