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 and executive qualifications shall be found.

Section 3.—That the Secretary of the Navy may detail for duty as astronomers at the National Observatory such professors of mathematics and other officers of the Navy as he shall deem necessary in the interests of the public service; but on and after the passage of this act no appointments shall be made of such professors unless required for service at the Naval Academy.

Section 4.—That there shall be a Board of Visitors of the National Observatory, to consist of one Senator, one member of the House of Representatives, and three astronomers of eminence, to be selected by the Secretary of the Navy. The Board of Visitors shall make an annual visitation, or more frequent visitations, of the Observatory, advise with the director thereof as to the scientific work to be prosecuted, and report to the Secretary of the Navy on the work and needs of the observatory on or before the first day of November in-each-year. The members of the said board may receive an allowance not exceeding ten dollars per day each during their actual presence in the city of Washington while engaged on the duty of the board, and their necessary traveling expenses; but no officer of the Government appointed on the board shall receive any additional compensation for such duty above his actual expenses.

probability that a National Standardizing Bureau will be authorized by the present Congress adds interest to the plans of the National Physical Laboratory recently established in Great Britain. Experimental work, somewhat limited in character, has for a long while been carried on at Kew Observatory, and it was hoped that the new laboratories might be erected near by. Plans were drawn up for a physical building to cost $30,000, and an engineering building to cost $20,000. There was, however, opposition to the erection of these buildings in the Old Deer Park, and in October the Government decided to assign to the laboratory Bushey House and the surrounding grounds, 25 acres in extent. The building as it now stands will be turned into a laboratory for the more delicate measurements, and a new laboratory for engineering will be erected. The work that it is proposed to carry out, as soon as the buildings can be occupied, includes the connection between the magnetic quality and the physical, chemical and electrical properties of iron and of its alloys, the testing of steam gauges and various kinds of springs, standard screws and electrical measuring instruments, and optic and thermometric determinations. These subjects have an evident connection with trade and industry, and there is every reason to suppose that the cost of the laboratory will be saved many fold every year by economies in the arts and manufactures, while at the same time physical measurements can be carried out in an institution of this character which no university would be likely to undertake. It should be noted that the National Physical Laboratory is under the direct control of the Royal Society, which insures the highest attainable degree of efficiency.

A valuable contribution to the study of the inert gases of the atmosphere is made by Professors Liveing and Dewar in a paper read before the Royal Society on December 13. The gases were obtained by liquefying air by contact with the walls of a vessel at atmospheric pressure cooled below 7 200° C. Some 200 ccm. of liquid air were thus condensed, and the more volatile portion was then distilled over into a receiver cooled with liquid hydrogen. This portion, consisting of about 10 ccm. was then passed into spectrum tubes, first, however, traversing a U-tube immersed also in liquid hydrogen. In this manner the gas was completely freed from every trace of nitrogen, argon and compounds of carbon. The tubes showed the spectra of hydrogen, helium and neon with great brilliancy, but also a large number of lines which could not be referred to any known origin. This shows conclusively that a sensible proportion of hydrogen exists in the earth's atmosphere, a point which has been much disputed in the past. If it be true,