252 



NATURE 



[AUGUS 



923 



taking their places in regular fashion on the surfaces 

 of the original crystal ; but aggregating themselves 

 about certain minute elementary crystals formed 

 on the surface, which act as " buds ' about which 

 further growth takes place. When the pressure and 

 temperature of the oven are high, this takes place 

 from the commencement, and there is no regular 

 crystal growth ; but a deposit is formed in scaly 

 layers round the original wire, which is either spongy 

 or dendritic in character. 



At the correct temperature and pressure the wire 

 will continue to grow as a single crystal in spite of 

 preliminary deformations, such as twisting, winding 

 into a heiix, or even drawing through a die. An 

 attempt was made to draw down the annealed 

 cultivated crystal into a fine wire, in the hope that 

 further cultivation would be possible upon it ; but 

 this failed owing to the fact that the whole pressure 

 coming on the edges overloaded the structure. The 

 resulting wire no longer formed a single crystal ; and 

 when additional tungsten vapour was deposited on 

 it, each of the small crystals of which it was composed 

 grew independently ; the resulting wire was brittle, 

 and could not be made flexible by heating. A similar 

 result was obtained with an ordinary tungsten wire, 

 which did not consist of a single crystal ; in this case 

 it was found that heating to 2500° C. for fifteen 

 minutes caused a great many of the small crystals 

 formed at first to unite, so as to give a much coarser 

 structure. This welding of small into larger crystals, 

 without mechanical pressure, has not, apparently, 

 been previously observed. 



State Afforestation in 1921-22.^ 



'T^HE Forestry Commissioners, who have just issued 

 ^ their third annual report, were appointed in 

 November 1919, to carry out a definite programme 

 of afforestation, involving the planting of 150,000 

 acres of new land in the ensuing ten years, the cost 

 to be defrayed from the Forestry Fund, a sum of 

 3,500,000/. voted by Parliament for the whole period. 

 Acquirement of land, planting operations, and other 

 activities, including education and research, were 

 proceeded with according to plan during the first 

 two years ; but the unfavourable financial position 

 of the Government necessitated a reduced programme 

 in the third year, so far as expenses were met with 

 out of the Forestry Fund. Fortunately the Com- 

 missioners obtained a large grant out of the Un- 

 employment Fund, and their operations have 

 practically not been restricted. During the year 

 ended September 30, 1922, the Commissioners 

 expended 244,414/. out of the Forestry Fund, and 

 154,017/. out of the Unemployment Fund, in all 

 398,431/., a sum in excess of the normal programme. 



The new land acquired for State afforestation 

 during 1921-22 amounted to 23,937 acres. The 

 Commissioners now possess 92,426 acres of plantable 

 land. The area planted by the Commissioners in 

 the year was 10,693 acres ; and in addition to this, 

 10,192 acres were planted by private owners and 

 corporations by means of grants, which were given 

 on condition that unemployed labour should be 

 used. These figures are very satisfactory. The 

 usefulness of forestry for relief work is abundantly- 

 shown in the report, which is replete with statistics 

 of the areas and species in the various plantations 

 and nurseries. 



Grants in aid of higher forestry education, in all 

 -2206/., were given to the University schools at Oxford, 



1 Third Annual Report of the Forestry Commissioners. Year ending 

 September 30, 1922. (H.M. Stationery Office, 1923.) Price is. net. 



Cambridge, Bangor, Armstrong College, and the two 

 Agricultural Colleges at Aberdeen and Glasgow. 

 The Commissioners have now three schools for 

 training woodmen, at Parkend (Forest of Dean), 

 Chopwell (Co. Durham), and Beauly (Inverness-shire), 

 at an annual cost of 10,160/. On research and 

 experiment, the expenditure was 6126/. Experi- 

 mental plots of various species of trees are now 

 120 in number. Investigations are being carried 

 out in regard to Chermes, Phomopsis Douglasii, tree 

 growth on peat, larch hybridisation, etc. ; and a M 

 census of woodlands is in progress. ^ 



The British Medical Association. 



T 



[""HE meeting of the British Medical Association 

 at Portsmouth began on July 20, and the 

 address of the president, Mr. C. P. Childe, was given 

 on the evening of July 24 to a large audience, among 

 whom were a number of distinguished visitors largely 

 from the Oversea Dominions. The president in his 

 address made a strong plea for better hoasing con- 

 ditions in the industrial centres, and insisted that an 

 enormous amount of the time and money which is 

 at present being spent on the treatment of diseases 

 like rickets and tuberculosis could be saved if adequate 

 care were given to the housing problem, for in his 

 opinion the absence of fresh air and sunlight in many 

 of the crowded industrial centres was in itself largely 

 responsible for the widespread occurrence of ttiese 

 diseases. 



The detailed work in the sixteen different Sections 

 went on from July 25 to July 27, during which a 

 very wide field of subject was under discussion. 



In the Section of Pathology and Bacteriology there 

 were discussions upon diseases of the stomach and 

 their methods of investigation, by Dr. C. Bolton ; 

 the value of serological tests in diagnosis, by Prof. 

 H. R. Dean; and one on the part played by fungi 

 in disease, by Dr. Castellani. Demonstrations were 

 given, in the afternoons, of specimens which had 

 been collected, forming a museum of very great 

 interest. 



In the Section of Radiology a discussion was 

 opened by Dr. R. W. Salmond on the X-ray examina- 

 tion of the urinary tract. During the discussion it 

 was evident that different weight was given by 

 radiologists to the value of screen examinations of 

 the region of the kidney. 



The second subject for discussion in this Section 

 was that of medical diathermy, opened by Dr. E. P. 

 Cumberbatch, and followed by Dr. C. A. Robinson, 

 who gave a detailed account of the treatment of 

 gonorrhcea by means of diathermic currents ; the 

 temperature which can be tolerated by the tissues 

 is sufficiently high to cause the death of the causative 

 micro-organism, and beneficial results ensue. 



In the Section of Tuberculosis a discussion was 

 opened by Prof. Reyn, of Copenhagen, on the subject 

 of the artificial light treatment of lupus and other 

 forms of tuberculosis. From the clinical investiga- 

 tions which have been continued during a large 

 number of years at Copenhagen, the conclusion has 

 been reached that the results obtained in the treat- 

 ment of lupus by means of ultra-violet light, initiated 

 there by Finsen, are much improved if the local 

 intensive treatment is supplemented by a general 

 irradiation of the whole body. Dr. Sequeira reported 

 a similar result from his experiences at the London 

 Hospital ; Prof. Russ thought that it was now 

 possible to assign to certain parts of the spectrum 

 their particular function in this form of therapy, and 

 if this were the case selection of the best form 



NO. 2807, VOL. I 12] 



