Among the advantages of Linde's liquid-air process, Prof. J. A. Ewing, speaking at the English Society of Arts, claimed its giving a means of separating more or less completely the oxygen of the atmosphere from its associated nitrogen. After describing a process by which a liquid consisting largely of oxygen may be produced, the author said that the most interesting application of the liquid which had hitherto been tried on a commercial scale was to make an explosive by mixing it with carbon. When liquid air, enriched by the evaporation of a large part of the nitrogen, was mixed with powdered charcoal, it formed an explosive comparable in power to dynamite, and which, like dynamite, could be made to go off violently by using a detonator. The chief advantage of the explosive was its cheapness, the cost being only that of liquefying the air. Even the fact that after a short time the mixture ceased to be capable of exploding might be urged as a recommendation, for if a detonator hung fire, there was no danger of the charge going off accidentally some time after the explosion was due, nor was there any risk of its being purloined or used for criminal purposes. NOTES. According to the _Tribune de Genève_, twenty new hotels were opened in Switzerland in 1897, and twenty-five were enlarged, adding two thousand beds and making the whole number of beds about ninety thousand. The number of nights' lodgings furnished during the season is estimated at ten million. Supposing each guest to spend twelve francs a day, the total revenue from tourists would amount to one hundred and twenty million francs, or twenty four million dollars. Classifying the guests according to nationality, it is estimated that the Swiss constitute eighteen per cent of the whole, Germans thirty-four per cent, English sixteen per cent, French twelve per cent, Americans eight per cent, and those of other nations twelve per cent. A list of women astronomers, compiled by Herman S. Davis from Ribiere's _Les Femmes dans la Science_, contains as contemporary workers in the science the names of seventeen American women who have taken part in astronomical computations or are teachers of astronomy, and twelve who are working in the application of photography to astronomy. Of the women in the later list, Miss Ida C. Martin, Miss Dr. Dorothea Klumpke (now in the Paris Observatory), and Mrs. M. P. Fleming have attained distinction for successful original researches.