July 14, 1904J 



NA TURE 



259 



I\". Reports. 

 Part i. of the twenty-fourth annual report for 1902-3 

 contains an account of the progress of the Survey by Mr. 

 C. D. Walcott, director, who refers to the increase of work, 

 and to the establishment of a separate hydrographic depart- 

 ment under the charge of Mr. F. H. Newell. An obituary 

 memoir, accompanied by a portrait, is given of Major 

 J. W. Powell. 



The detailed report on the " Mineral Resources of the 

 United States," for 1902, by Mr. David T. Day, shows a 

 continuation of the remarkable activity in the mineral 

 industries, the total value exceeding one thousand million 

 dollars — iron and coal being the most important products. 

 There was a notable increase in the production of uranium 

 and vanadium minerals, and these were nearly all shipped 

 abroad in the crude state as mined. The production of 

 bauxite was largely increased, while that of monazite, 

 obtained chiefly from North Carolina and partly from South 

 Carolina, showed a slight increase over the previous year. 

 The production of crude petroleum and of natural gas also 

 <:howed increase. 



V. Local Surveys. 

 The Wisconsin Geological and Natural Historv Survey 

 has sent copies of Bulletins Nos. n and 12. The former is 

 a " Preliminary Report on the Soils 

 and Agricultural Conditions of the 

 North-central Portion of the State," 

 by Dr. S. Weidman. It is illus- 

 trated by a soil map, on the scale 

 of an inch to three miles, and this 

 gives the general character of the 

 soil over different " soil formations " 

 or subsoils — in reality various al- 

 luvial and drift deposits. No. 12 is 

 by Mr. C. D. Marsh on " The 

 Plankton of Lake Winnebago and 

 Green Lake," lakes of different 

 types, one shallow, the other deep. 

 As bearing on the question of fish- 

 production, it is noted that Entomo- 

 straca, which furnish the basis of 

 food for fishes, are more numerous 

 in the deep than in the shallow lake. 

 We have received also vol. xiii. 

 of the Memoirs of the Iowa Geo- 

 logical Survey, being the annual 

 report for 1902 with accompanying 

 papers. The papers comprise de- 

 scriptions (seven in number) of 

 various counties, by the State 

 Geologist, Mr. Samuel Calvin, and 

 his assistants. There is also a dis- 

 cussion of the requisite qualities of 

 iithographic limestone, with a re- 

 port on tests of the lithographic 

 stone of Mitchell County, Iowa, by 

 Mr. A. B. Hoen. The report is 

 accompanied by a colour-printed 



plate drawn on the local stone and illustrating the quarry 

 from which it was obtained. The sample, submitted for 

 trial, was not wholly satisfactory, inasmuch as it was 

 noticed in trueing the stone for printing that the surface- 

 plane intercepted planes of bedding at small angle, but 

 there is reason to hope that, as the stone is worked, larger 

 and more perfect slabs may be obtained. H. B. W. 



by sanitary authorities. As the steam penetrates into the 

 interstices of the colder articles it undergoes condensation, 

 and imparts its latent heat instantaneously to the colder 

 objects in contact with it. Steam thus condensed into water 

 occupies only a very small fraction (about 1/1600) of its 

 former volume, and to fill the partial vacuum thus formed 

 more steam presses forward, in its turn becoming con- 

 densed and yielding up its latent heat, and so on until the 

 whole mass has been penetrated. 



Saturated steam may be used as current steam at* about 

 atmospheric pressure ; but there is an advantage, in point 

 of time, in the employment of steam disinfecting apparatus 

 in which saturated steam is used under pressure, and higher 

 ternperatures are thereby obtained, when very highly 

 resistant organisms have to be destroyed. 



The time required for disinfection by steam obviously 

 depends upon the resistance of the organism to be de- 

 stroyed, the bulk of the infected articles, and the pressure 

 of the steam employed. The best researches indicate a 

 pressure of 10 lb. (and therefore a temperature of 115° C.) 

 for twenty minutes as trustworthy in general practice. 



The steam may be generated in a special boiler, from 

 whence it is conducted to the disinfecting chamber, and 

 such a boiler is sometimes made to supply steam for laundry 

 purposes ; or the lower part of a jacketed oven mav be 



:. — Interior 



fecting Station. 



DISINFECTING STATIONS. 

 A N interesting article upon disinfecting stations, written 

 -^"^ by Prof. Henry R. Kenwood and Mr. P. J. Wilkin- 

 son, appears in the most recent issue of the Journal of the 

 Sanitary Institute (vol. .x.xv., part i., .'\pril ; London : Offices 

 of the Sanitary Institute, Parkes' Museum, Margaret 

 Street, W.). 



It is now well recognised that the disinfection of textile 

 articles can be effected by the use of steam more quickly, 

 more certainly, and with less damage to the article dis- 

 infected than by the use of any other agent ; and a steam 

 disinfecting station is now considered an essential provision 



NO. 181 I, VOL. 70] 



filled with water, and by firing directly under the machine 

 the steam may be raised in the jacket of the disinfector 

 itself. This arrangement favours compactness and 

 economy, but a separate boiler is more accessible for 

 cleansing and repairs. 



The various stoves now employed for disinfecting by 

 steam may be classified as follows : — 



(i) Stoves in which steam without pressure is employed. 

 These are, of course, the simplest and cheapest. 



(2) Those in which steam at low pressure (2, 3 or 5 lb. 

 per sq. in.) is used. Although the temperature of 110° C. 

 which can be reached by some of these stoves is generally 

 sufficient, a higher temperature can never be employed in 

 them. These stoves, though cheaper, meet with less general 

 acceptance in this country than 



(3) Those in which steam at high pressure (10 lb. and 

 over) can be employed. 



.A. temperature of 115° C. to 120° C. can be obtained in 

 these stoves, and an exposure of articles for about twenty 

 minutes will suffice for disinfection. 



-A disinfection station should comprise : — 



(i) Two rooms completely separated from each other by 



