Januaet 21, 1910] 



SCIENCE 



103 



the Eoyal Society," as it was termed by Davy 

 — in 1904. Three times has he been the 

 Bakerian lecturer of the Eoyal Society. 



Crookes has published the following trea- 

 tises: "On Thallium" (1863); "On the 

 Manufacture of Beet Boot Sugar in Eng- 

 land and Ireland" (1870); "Select Methods 

 in Chemical Analysis" (18Y1, 1886, 1888, 

 1895) ; " A Practical Handbook of Dyeing and 

 Calico Printing " (1874, 1883) ; " Dyeing and 

 Tissue Printing " (1882) ; " La Genese des 

 Elements" (1887); "Die Genesis der Ele- 

 mente " (1888) ; " Elements et meta-Ele- 

 ments " (1888) ; a translation of Eudolf von 

 Wagner's " Die Chemische Technologie " 

 (1872, 1881, 1892) ; and several other less im- 

 portant translations and editions of German 

 and French works on chemical subjects. 



The list of his scientific papers would be too 

 long to present here, but it may be said that 

 Sir William Crookes is an authority on the 

 rare earths and rarer elements, and on spec- 

 troscopy and sanitary science. 



His investigations on the rare earths have 

 been chiefly on the phosphorescence spectra 

 of yttrium, samarium (cathode-luminescence 

 spectrum) and erbia (luminescence spectrum) ; 

 on the absorption spectrum of didymium; 

 and on the separation of these earths and their 

 distribution (universal distribution of yttrium 

 and scandium). In 1899, Crookes announced 

 the existence of a new element, victorium, 

 earlier called monium, and previously (in 

 1886) he claimed to have discovered two new 

 elements, ionium and incognHum. In 1876, 

 Crookes devised the well-known " Crookes 

 Tube," and in 1903 the spinthariscope. His 

 investigations of the radio-active elements 

 have also been noteworthy, and in 1900 he 

 fractioned uranium nitrate into an inactive 

 product, thereby obtaining an active sub- 

 stance, Ur-X. 



In sanitary science, the important work of 

 Crookes has been on sewage disposal, on 

 water supply and contamination, on the use 

 of disinfectants, and on the wheat problem. 



Crookes has delivered the following ad- 

 dresses : " On Eadiant Matter " (British As- 

 sociation, Sheffield Meeting, August 22, 1879) ; 

 " On Eadiant Matter Spectroscopy " (Baker- 



ian Lecture, Eoyal Society, May 31, 1883) ; 

 address to the chemical section of the British 

 Association, Birmingham Meeting, September 

 2, 1886, dealing with the nature and origin 

 of the so-called elements ; " Genesis of the 

 Elements " (Eoyal Institution, February 18, 

 1887) ; address as president of the Chemical 

 Society, anniversary meeting, March 28, 

 1888 ; " On Eeeent Eesearches on the Eare 

 Earths " (annual general meeting of the 

 Chemical Society, March 21, 1889); "Dia- 

 monds " (Eoyal Institution, June 11, 1897) ; 

 British Association Inaugural address, Bris- 

 tol, 1898, dealing mainly with the " Wheat 

 Problem " ; and his admirable lecture on 

 " Diamonds " before the British Association, 

 Kimberley meeting, September 5, 1905. 



Sunday evenings. Sir William is at home. 

 Within his study walls, bebooked to the ceil- 

 ing, one may find then the finest minds of 

 science in England or other lands, grappling 

 in discussion with the unsolved problems, 

 which oftentimes become no clearer than the 

 increasing denseness of the tobacco smoke. 

 Promptly at eleven o'clock there comes a 

 bright rift in the clouds as Lady Crookes enters 

 and charmingly leads all to the dining room 

 below. 



Punctilious in the performance of every 

 duty, courteous but vigorous in argument, 

 modestly assertive, learning from the young- 

 est. Sir William draws out the humblest until 

 he would become almost bold, yet, in return, 

 he gives generously from his rich store of wide 

 knowledge and large experience. Such is the 

 man the trustees would have the club honor 

 and thus gain luster itself, for William 

 Crookes, the savant, ornaments any company, 

 and his life work is an inspiration for the 

 present generation and the generations of 

 men of science to come. 



THE INTERNATIONAL AMERICAN CON- 

 GRESS OF MEDICINE AND HYGIENE 

 The International American Congress of 

 Medicine and Hygiene of 1910 in commemora- 

 tion of the first centenary of the May revolu- 

 tion of 1810, under the patronage of his excel- 

 lency, the President of the Argentine Eepublic, 



