Januakt 29, 1904.] 



SCIENCE. 



197 



pexata, Eupagurus pollicaris, Osirea virgin- 

 iana and Cancer irroratus. 



The significance of this unique occurrence 

 of zinc in the economy of Sycotypus and 

 Fulgur is still to be determined, as is the 

 nature of the combination in which it exists. 

 These points, together with the distribution of 

 the element in other marine forms about the 

 sound, are at present being investigated and 

 will be reported upon later. 



Harold C. Bradley. 



Sheffield Laboratory op Physiological 

 Chemistry, Yale University. 



ATMOSPHERIC NITROGEN FOR FERTIL- 

 IZING PURPOSES. 

 Of much interest to scientific students of 

 agricultural economy is the report of the 

 United States Consul-General Mason, at 

 Berlin, Germany, on a new method of pro- 

 ducing nitrogen from the atmosphere for soil 

 fertilization, as announced in the daily ' Con- 

 sular Eeport,' ISTo. 1804, issued by the Bureau 

 of Statistics, Department of Commerce and 

 Labor. 



The gradual but ultimately inevitable ex- 

 haustion of the known nitrate deposits of 

 South America, the report states, lends a 

 growing interest to the methods which have 

 been devised for obtaining a supply of nitro- 

 gen for fertilizing purposes from the inex- 

 haustible storehouse of the air. That this can 

 be done as a scientific process has long been 

 known. The first method was by passing a 

 current of air over red-heated copper, whereby 

 the oxygen combined with the metal to form 

 oxide of copper, leaving the nitrogen free. 

 At first the nitrogen thus produced was fixed 

 by combination with calciimi carbide to form 

 nitrate of lime (Kalkstickstoff) or calcium 

 cyanimide, a combination of lime carbon and 

 nitrogen, which had all the essential properties 

 of a nitrate fertilizer. But as the use of 

 calcium carbide rendered the product unduly 

 expensive, a method was sought which would 

 employ a substitute for that material, and this 

 was found by Dr. Erlwein, who brought the 

 nitrogen into combination with a mixture of 

 powdered charcoal and lime in an electric 

 furnace. The product of this combination is 



a black substance containing, besides the lime 

 and carbon, ten to fifteen per cent, of nitrogen, 

 in perfect condition to be used as a fertilizer. 

 From the experiments thus far made with this 

 new artificial nitrate — which is known in com- 

 merce as calcium cyanimide — it appears that 

 its nitrogen acts upon plants quite as effect- 

 ively as that contained in a proportionate 

 quantity of nitrate of potassium or sodium 

 nitrate (Chile saltpeter). The scientific prob- 

 lem of obtaining nitrogen for fertilizing pur- 

 poses from the atmosphere would seem, there- 

 fore, to be satisfactorily solved. Whether it 

 can be done on a very large scale and at a 

 cost which will make it economically available 

 for general agricultural purposes remains to 

 be demonstrated by practical experience. 



John Franklin Ceowell. 



MISSOURI LEAD AND ZING REGIONS 



VISITED BY THE GEOLOGICAL 



SOCIETY OF AMERICA. 



At the close of the St. Louis meeting of the 

 Geological Society of America, January 2, an 

 excursion to the Missouri lead and zinc re- 

 gions was given by the Missouri Bureau of 

 Geology and Mines to the members of the so- 

 ciety whose work would allow them time for 

 the journey. In the company several univer- 

 sities were represented — ^Alabama, Dartmouth, 

 Kentucky, McGill, Missouri, Northwestern, 

 Rochester, Springfield and Toronto, and sev- 

 eral members of geological surveys were pres- 

 ent — Geological Survey of Canada, Missouri, 

 Ontario, West Virginia and the United States. 

 The excursion allowed of a view of the Mis- 

 souri geological scale from the St. Louis for- 

 mation (of the sub-Carboniferous), through 

 Devonian, Ordovician, Cambrian to the Al- 

 gonkian, and many phases of geology, from 

 peneplain to paleontology, had their share of 

 attention. However, the chief place in the 

 thought of the visitors was occupied by the 

 mineral resources of the famous lead and zinc 

 localities. A day and a half was spent in the 

 eastern lead region — the classical locality for 

 lead production in the Mississippi valley. A 

 number of mines and mills at Bonne Terre 

 and Central were visited, and the facts ob- 

 tained there, when combined with those ob- 



