December 22, 192 1] 



NATURE 



541 



violet light for the purposes of invisible signalling 

 to the investigation of sole leather for boots, but 

 the report being arranged alphabetically, they 

 come in close proximity therein. Perhaps this is 

 well, for it indicates the widespread activities of 

 the Bureau. Not only were the wearing proper- 

 ties of various soles, made of both leather and 

 composition, tested, but a radiographic study of 

 the clinching of the nails used in repairing the 

 soles was also undertaken. 



The work of the metallurgical department 

 ranged between such widely different problems as 

 the investigation of nails for horse-shoes and the 

 studv of gold-palladium alloys as substitutes for 

 platinum. As is to be expected, the study of light 

 (aluminium) alloys, largely in connection with air- 

 craft requirements, occupies a prominent place. 

 It is stated that the work to date has shown the 

 superiority of alloys containing either copper and 

 zinc or magnesium and copper as additions to 

 aluminium, and it is of interest to note that the 

 Bureau concentrated on magnesium-copper- 

 aluminium alloys because the National Physical 

 Laboratory was, at the time, investigating copper- 

 zinc-aluminium alloys. In connection with these 

 materials attention must be directed to the curious 

 phrase referring to " the French alloy Duralumin," 

 while later Wilm is correctly referred to as the 

 discoverer of the hardening of this alloy after heat 

 treatment. 



Another use to which an aluminium alloy was 

 put was for the manufacture of mirrors of high re- 

 flecting power, it being found that the compound 

 Al3Mg4, containing 50 per cent, of magnesium, 

 gave a reflection of 85 per cent, in the 

 blue and 93 per cent, in the red portions of the 

 spectrum, though such mirrors are not recom- 

 mended where permanency is of prime importance. 

 It may be of interest to note that the recent work 

 of Hanson and Gayler, at the National Physical 



Laboratory, throws considerable doubt on the 

 existence of this compound. 



Amongst the many other metallurgical re- 

 searches undertaken, two may be selected for men- 

 tion; one is an investigation on the welding of 

 steel, and the other a series of tests on different 

 compositions of bearing metals. 



The production and testing of optical glass are 

 other branches of the activities of the Bureau 

 which call for special mention. The manufacture 

 was commenced in 1914-15 — before America de- 

 clared war — and in 19 17 a large furnace holding 

 a looo-lb. pot was built, in which glass was pro- 

 duced on a commercial scale, and very satisfactory 

 results were obtained. 



Brief reference only can be made to other in- 

 vestigations described in the report. The photo- 

 graphic work, especially illustrating a view taken 

 from an aeroplane through a haze, (i) on an 

 ordinary plate, and (2) on a plate specially pre- 

 pared at the Bureau, is of great interest. A very 

 large amount of work on radio-communication, 

 including special investigations on direction-find- 

 ing and on signalling from submerged submarines, 

 is also described. Investigations on rubber for 

 tyres, insulated wire, etc., and work on sound- 

 ranging and on sound transmitted through the 

 earth, which was a development of British and 

 French methods, also deserve mention. Work on 

 textiles covers a very wide range of 

 subjects, including some research on dye- 

 stuff chemistry. Finally, there is the work on 

 X-rays, which, however, was not initiated until 

 1917. 



The Bureau of Standards is to be congratulated, 

 not only on the immense amount of useful war 

 work which it has carried out, but also on the 

 interesting manner in which it has presented the 

 summarv of this work to the public. 



J. L. H. 



Obituary. 



The Right Hon. Lord Lindley, P.C, F.R.S. 



THE name of the Right Hon. Lord Lindley, 

 whose death, in his ninety-fourth year, occurred 

 at East Carlton, Norwich, on December 9, will long 

 be remembered as that of a distinguished lawyer 

 and a great judge. The features in Lord Lindley's 

 judgments which arrested attention were themselves 

 due to the remarkable scientific instinct with which 

 they were imbued. This quality may have been in- 

 herited, for the same independence and sagacity, 

 displayed in another sphere, mark the writings of 

 Lord Lindley's father, Dr. John Lindley, F.R.S. , 

 professor of botany at University College, and for 

 many years the editor and principal proprietor of 

 ■'.e Gardeners^ Chronicle. 



The constant intercourse between Prof. Lindley 



■id Sir William Hooker, director of Kew during 



:S4i-65, brought young Lindley into contact with 



Dr. (afterwards Sir Joseph) Hooker, assistant 



urector of Kew from 1855, and Sir William's suc- 



"ssor in the directorship during 1865-85. The fast 



NO. 2721, VOL. 108] 



friendship and constant correspondence thus initi- 

 ated ended only with the death of Sir Joseph in 

 191 1. This correspondence, it is fair to state, rarely 

 related to technical botanical subjects. On the con- 

 trary, it indicates rather that Lindley and Hooker, 

 who often consulted each other on important matters 

 of business, each placed implicit reliance on the 

 \ judgment of the other as to questions which con- 

 cerned their own particular activities. But while it 

 is doubtless true that the keen interest which Lord 

 Lindley, throughout his long life, took in botanical 

 pursuits was strengthened by his friendly relation- 

 \ ship with Sir Joseph Hooker, it is unquestionable 

 i that it had its foundation in his admiration for, and 

 I sympathy with, his father's work. His interest led 

 \ to intimate intercourse with other prominent con- 

 temporary botanists, notably with the late Mr. 

 , George Bentham, joint- author with Sir Joseph 

 I Hooker of that remarkable work, the " Genera Plan- 

 tarum." 



Equally keen throughout his life was the sym- 



