^OA 



ATA TURE 



[February 27, i( 



adduced the photographs as he interprets their features as 

 corroborating his own observations, forgetting that this 

 implies that he sees the originals only a fraction as well 

 as he should. 



Yet even so the photographs have surpassed our hopes, 

 for they disclose more than one could have ventured to 

 imagine. An eye versed in photographic perception and 

 interpretation will easily see in them the canals as lines 

 and the little spots, the oases, at their junctions. Indeed, 

 the camera has shown itself capable of rising beyond the 

 confirmatory into the discovery stage ; for one of the 

 plates of the writer was instrumental in the detection of 

 a new canal. A stranger appeared on the plate which 

 when searched for visually in consequence proved to be 

 there. At the next opposition, with our newly devised 

 improvements and with the planet so much nearer the 

 zenith for northern observers, it is confidently to be 

 expected that we shall do still more. 



Percival Lowell. 



HYDROLOGY IN THE UNITED STATES. 



T N some of the more recent reports on the hydrology of 

 ^ the United States, the book is prefaced by a general 

 statement as to the intention and scope of the surveys 

 that are being carried out by the geological department 

 of the Government relating to the water resources of the 

 country. 



Water supply is regarded as one of the principal national 

 assets, and of more importance to the life and pursuits 

 of the people than any other natural resource. In the 

 arid States the limit of agricultural development is deter- 

 mined by the amount of water available for irrigation. 

 In other States, where the rainfall is greater and more 

 evenly distributed throughout the year, the lack of rain 

 at the proper season often reduces a crop to one-half 

 what it would have been with one additional wetting at 

 the time most needed. Storage, providing water for use 

 when most wanted, will in such a case be as beneficial as 

 where irrigation has to be depended on exclusively. This 

 is especially the case in those districts where ' market 

 gardening is one of the most profitable agricultural pur- 

 suits. Here irrigation is a necessity for making the 

 business profitable. 



The increase in the population of cities and towns makes 

 necessary additional water supplies for domestic and 

 industrial uses, in procuring which both the quantity and 

 quality of the water that can be obtained must be 

 considered. 



The location of manufacturing plants may depend largely 

 on the water-power facilities and the character of "the 

 water. _ Electric transmission of power has led to the 

 utilisation of water-power for the operation of manu- 

 facturing establishments and lighting plants. Water- 

 power is also largely used in some States for log driving, 

 lumbering, and saw-mills, and also for the manufacture 

 of oaper from wood pulp and straw. 



For all or any of these purposes a knowledge of the flow 

 of the streams and of the conditions affecting that flow, 

 based on trustworthy data, and of the underground re- 

 sources is essential. For the want of this many schemes 

 for water supply have ended in failure, the plans being 

 made without sufficiently trustworthy information. 



The United States Geological Survev has therefore, by 

 means of appropriations by Congress', for several vear's 

 systematically been engaged in obtaining records of stream 

 flow, the number of stations at which streams were 

 under observation in igo6 being 700. Records are also 

 obtained in regard to floods, precipitation, the relation of 

 the rainfall to run-off of water, evaporation, water pollu- 

 tion, the flow of underground streams, the use of artesian 

 and surface wells, and generally all matters relating to 

 water supply. 



The reports relating to the above matters, and also as 

 to the water resources of different States and districts, 

 are ^ issupd from time to time, upwards of 200 reports 

 having- already been issued. 



Notices of these reports, directing attention especially 

 to those pnners which are of general interest, have 

 -tppeared in N.ituru at various times. 



'^<^. 2000. VOT. 77] 



The most recent reports of which we have received 

 copies,' eleven in number, relate to the water resources of 

 Georgia, New England, and other districts, the informa- 

 tion contained in them being principally of local interest, 

 except Paper No. 201, which has an introduction dealing 

 with the system followed in obtaining the discharge of 

 streams. 



r//E TESTING OF MATERIALS. 



'T~'HE official report of the proceedings of the fourth 

 Congress of the International Association for the 

 Testing of Materials was recently issued. The congress 

 was held at Brussels in September, 1906, and the report 

 contains a condensed account of the reports presented and 

 a summary of the discussions upon the reports and papers. 

 The congress met in three sections, one dealing with 

 papers on metals, another with papers on cement and 

 artificial stones, and the third dealing with miscellaneous 

 investigations, such as protection of metals against rust, 

 testing of timbers, rubber, &c. Before the sections began 

 their proceedings, Prof. Schiile delivered an address deal- 

 ing with the life and work of the late president and 

 founder of the association, Ludwig von Tetmajer. 



One of the most important matters discussed in thr- 

 metal section was the method of testing notched bars : 

 after a lengthy discussion the congress eventually adopted 

 the following resolution : — " The congress recognises that 

 the method of testing notched bars appears capable of 

 giving extremely interesting results." The congress did 

 not, however, adopt a resolution which was moved to the 

 effect that the method should be experimentally introduced 

 into certain specifications. 



In regard to the subject of ball-pressure tests, the 

 congress eventually adopted the following resolution : — 

 " The present congress desires that in the acceptance of 

 metallic materials tests of tenacity should be supplemented 

 as often as possible by a determination of the Brinell 

 hardness numbei", the latter test being performed for the 

 obiect of collecting information." 



During the meeting of the association a metal-testing 

 laboratory was installed at Brussels in order to show in 

 action the various modern processes employed in the test- 

 ing of materials. The tests made were micrographir. 

 determination of the critical points, impact tests on notched 

 bars, Brinell ball tests, and shearing tests. The congress 

 has published a small illustrated pamphlet descriptive of 

 the various testing appliances which were at work in this 

 metal laboratory, with a brief note on the results obtained. 



T. H. B. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — The Vice-Chancellor gives notice that the 

 election of a professor of agricultural botany will take 

 place on Monday, March 16. Candidates for this oro- 

 fessorship are requested to communicate with the Vice- 

 Chancellor on or before Wednesday, March 11. 



Sir Ernest M. Satow, G.C.M.G., has been appointed to 

 the office of reader on Sir Robert Rede's foundation for 

 the present year. The lecture will be given in the Senate 

 house on Saturday, June 13. 



LoxDON. — In connpction with the supplementary vote of 

 6000?. for the Imperial College of Science and Tecbnologv 

 at .South Kensington, being part of the annua! Govern- 

 ment subvention of 20.000;. to the college. Sir Philip 

 Magnus inquired last Friday in the House of Commons 

 whether the 20,000?. was in excess of the cost of main- 

 tenance of the Royal College of Science and the Royal 

 School of Mines, which had been incorporated in the 

 Imperial College. In reply, Mr. Lough explained that the 

 grant of 20,000/. was arranged by the Board of Education 

 under the late Government; in addition, the Imperial 

 College would have the fees paid by students, including 

 fees paid by the Board of Education for scholars nominated 

 by the Board. In reply to a further inquiry by Sir Philip 



1 Water Supply and Irrigation Papers. (Washington : d 

 Printing Office.) 



