680 



SCIENCE 



[N. S. Vol. XXVIII. No. 724 



presented anonymously in German, English or 

 French, not later than the end of 1911, to the 

 secretary of the society. Professor G. Hell- 

 mann, Berlin W., 56. Shinkelplaz 6. 



The exhibit on the ground floor of the 

 American Museum of Natural History illus- 

 trating the solar system has been altered so as 

 to be more comprehensive and instructive. 

 The sun is now represented by an illuminated 

 globe three inches in diameter, which brings 

 the orbit of the earth just within the foyer. 

 The foyer, therefore, now contains the whole 

 of the orbits of Mercury, Venus and the earth 

 and part of that of Mars, while the adjoining 

 exhibition halls contain the remainder of the 

 orbits of Mars and parts of those of Jupiter 

 and Saturn. The orbits are represented by 

 circles of wire on which the days and months 

 are indicated and along which the planets, 

 shown as lights of proper size, are moved from 

 day to day in correct position. 



The production of quicksilver in the United 

 States in 1907, as shown by confidential re- 

 turns to the United States Geological Survey 

 from every producing mine in the country, 

 amounted to 21,567 flasks of 75 pounds each, 

 and was valued at $828,931, the figures show- 

 ing a decrease, when compared with those for 

 1906, of 4,671 flasks in quantity and of $129,- 

 703 in value. A detailed report on the in- 

 dustry, prepared by H. D. McCaskey, geolo- 

 gist of the survey, has been published in an 

 advance chapter from " Mineral Resources of 

 the United States, Calendar Tear 1907." An 

 output of quicksilver was reported from but 

 three states in 1907 — California, Texas and 

 Utah — and the single producer in Utah re- 

 ported no production for the last seven 

 months of the year. A small amount was re- 

 ported from Oregon in 1906, but none at all 

 in 1907. In California, which furnishes about 

 80 per cent, of the domestic production, the 

 industry was not in a very flourishing condi- 

 tion during the year. The returns from the 

 state show a decrease of 2,879 flasks in 

 quantity and of $68,26-1 in value from the pro- 

 duction of 1906— an output of 17,431 flasks, 

 valued at $662,544, having been reported in 

 the later year as compared with 20,310 flasks. 



valued at $730,808, in the earlier. The de- 

 crease in the hydraulic mining of gold, 

 formerly so important an industry in Cali- 

 fornia, the decreased amount of gold and 

 silver recovered by amalgamation process 

 alone, and the increased tendency to ship ores 

 of the precious metals to smelters have all 

 tended to reduce the local demand for quick- 

 silver. Statistics of world production of 

 quicksilver for 1907 are not yet available, 

 but a comparison of the figures for quantities 

 produced in foreign countries in 1906 with 

 those for the United States in that year shows 

 that this country ranked second among the 

 quicksilver producers in that year, Spain hav- 

 ing first place. Austria held third place, Italy 

 fourth and Russia fifth. Practically all of 

 the quicksilver product of Spain comes from 

 the famous old mines of Almaden, where 

 about 4,000 men are employed. It is probable 

 that these mines alone contain sufficient re- 

 serve ore to enable them to dominate the 

 world's market. 



In May, 1906, Dr. Sheffield Neave was asked 

 by the Tanganyilva Concessions, Limited, on 

 behalf of that company, of the Union Miniere, 

 and of the Benguella Railway Company, to 

 ascertain, in respect of the mining area of 

 Katanga, the distribution of the various 

 species of tsetse and other biting flies, to study 

 the distribution of sleeping sickness should it 

 be found to exist, and to investigate the blood 

 of the population in any infected area, to 

 make research generally in respect of the 

 disease in the concession and its neighborhood, 

 and to report and advise as to what measures 

 should be taken in respect thereto. The 

 author has now narrated his experiences in a 

 paper entitled Portions of Report on Work of 

 Katanga Medical Commission, 1906, 1907, 

 1908. An abstract in The British Medical 

 Journal states that a considerable portion of 

 the time was spent ascertaining the distribu- 

 tion of Glossina palpalis, but other research 

 work, when time permitted, was carried out. 

 Dr. Neave found that the most typical form of 

 enlarged glands containing trypanosomes was 

 that which included the following qualities: 



(1) A symmetrical enlargement on both sides; 



(2) chain formation as opposed to single 



