August S, 1907] 



NA TURE 



0/0 



programme of papers was arranged. Mr. William 

 Simpson's paper on granite quarrying in Aberdeenshire 

 was specially noteworthy in that it furnished information 

 on a subject regarding which the technical literature is 

 remarkably sparse. Nowhere in the whole of Great 

 Britain is there such a large exposure of granite as in 

 north-east Scotland, and the supply of granite of the 

 highest durability and beauty is practically inexhaustible. 

 The quarrying presents many features of difficulty. The 

 overburden is costly to remove, and the top rock un- 

 remunerative. As a rule the quality of the rock improves 

 with the depth, and there is a temptation to deepen with- 

 out a proportionate surface area. Where this has been 

 done the quarry has assumed the form of a conical pit 

 with a small floor, difficult and costly to work. Mr. 

 Herbert Bing submitted a paper on portable pneumatic 

 tools. Of recent years there has been great progress made 

 in these tools, and in the range of work to which they 

 are applicable. -At the present time they will be found 

 in use in practically all engineering works, shipyards, and 

 mines. Mr. C. E. Larard described an electrically con- 

 trolled single-lever testing machine at the Northampton 

 Polytechnic Institute, London. The machine constitutes 

 quite a new departure in many of its arrangements, and 

 has given very satisfactory results in testing, due primarily 

 to the good control over the rates of loading and strain- 

 ing. Papers were also contributed by Mr. J. M. Hender- 

 son, on cableways used on shipbuilding berths, and by 

 Mr. D. J. Macdonald, on jute preparing and spinning. 



Tn October, 1905, a committee was appointed by the 

 council of the Royal Institute of British Architects to 

 draw up rules for guidance in the use of reinforced con- 

 crete. The report of this committee has recently been 

 published, and in the Engineer of July 26 the rules drawn 

 up are compared with the French Government instruc- 

 tions. In the more important matters there is uniformity 

 in treatment, and the rules proposed by the committee are 

 by no means revolutionary. 



The fuels committee of the Motor Union of Great 

 Britain and Ireland has issued a valuable report on motor- 

 car fuels, of which a summary is published in the Engineer 

 of July 26. Readers of the report will find cause for a 

 despondent view of the petrol supply, and will probably 

 agree that a famine in petrol appears to be inevitable in 

 the near future, owing to the fact that the demand is 

 increasing at a rate much greater than the rate of increase 

 of the supply. In 1904 the consumption of petrol in the 

 United Kingdom was 12,000,000 gallons; in 1907 it had 

 risen to 27,000,000 gallons. In November, 1904, the trade 

 price was yd. per gallon ; in December, 1906, it was 13d. 

 Having recognised that the time is not far distant when 

 a substitute for petrol must be sought, the committee dis- 

 cusses in the report other possible fuels. The supply is 

 divided into two parts. The first includes all fuels limited 

 in quantity ; they are the spirits of a specific gravity 

 between petrol and paraffin, paraffin itself, coal dust, gas, 

 and benzol. The second group contains one item only — 

 alcohol — and it is evident from the whole tone of the 

 report that the committee expects to find in denatured 

 vegetable spirits the fuel of the future. 



An article on the natural regeneration of the " dhowra " 

 tree, Anogeissus latijolia, in the Panch Mahal division of 

 Bombay, is communicated by Mr. R. F. Pearson to the May 

 number of the Indian Forester. Owing to the occurrence 

 of a large number of trees of an even age, the author 

 was led to examine the conditions under which such 

 NO. I 97 I, VOL. 76J 



extensive seedling growth was developed. Whilst the rain- 

 fall in the year of germination was distinctly favourable, 

 the opinion is expressed that, in addition, the seed must 

 have been unusually fertile. The fertility of seeds from 

 trees is a question deserving the attention of foresters. 

 Mr. Pearson attributes the fertility of the seed in this 

 instance to the stimulus or shock caused by the drought 

 of the previous year. A note on the Kashmir trout 

 fisheries refers to the attempts, finally successful, made 

 by Mr. F. Mitchell whereby the Harwan stream and the 

 Dhal Lake have been stocked with brown trout. 



With reference to afforestation, in a paper printed in 

 the Transactions of the Royal Scottish Arboricultural 

 Society, vol. xx., part ii., Mr. A. C. Forbes discusses the 

 problem of planting up waste land, and places on record 

 certain data, obtained by the measurement of sample plots 

 of Scots pine, larch, and spruce on plantations in 

 Northumberland and Cumberland, showing an annual 

 increment varying from 50 cubic feet to 80 cubic feet per 

 acre. Figures are also presented, on the authority of 

 Lieut.-Colonel F. N. Innes, for plantations in Aberdeen- 

 shire. Other papers in the volume include a summary 

 of a paper by Mr. M. Henry on the interrelation between 

 forests and I'ainfall, arboricultural notes from Portuguese 

 East Africa contributed by Mr. J. A. Alexander, and an 

 account of the work at Eberswalde Forest Academy by 

 Mr. A. F. Wilson. 



A DISSERTATION On the physiological significance of 

 caffein and theobromin, by Dr. Th. Weevers, is published 

 in Annales du Jardin botanique de Buitenzorg, ser. ii., 

 vol. vi. These xanthin derivatives were found in all parts 

 except the roots of Thea assainica and Coffea arabica, but 

 only in the early vegetative stages of Coffea stenophylla 

 and Cola acuminata. From a comparison of the quanti- 

 ties obtained in young and maturing leaves, also in leaves 

 placed in air devoid of carbon dioxide, the author con- 

 cludes that these substances are formed as secondary pro- 

 ducts in the breaking down of proteins, and are sub- 

 sequently absorbed in protein synthesis ; in the seeds they 

 are plentiful, forming a nitrogenous reserve. 



A BULLETIN, No. 187, issued by the United States Depart- 

 ment of .Agriculture, deals with the digestibility and 

 nutritive value of legumes, recording the results of experi- 

 ments conducted by Dr. C. E. Wait at the L'niversity of 

 Tennessee. Although these tend to prove that legumes are 

 not so thoroughlv digested as many other foods, the 

 author recommends their inclusion as a source of protein 

 in the diet, and directs attention to the value of cow- 

 peas, the product of Vigna Catiang. 



We have received copies of two issues, No. 68, part i., 

 and No. 69, of the Bulletin of the U.S. Bureau of 

 Entomology, the former, by Mr. Dudley Moulton, dealing 

 with the pear-thrips (Eutlirips pyri), while in the latter 

 Mr. F. M. Webster discusses the ravages of the chinch- 

 bug (Blissus leucoptcrus). The pear-thrips flourishes in the 

 districts around San Francisco Bay and the Sierra Nevada 

 foot-hills, but whether it is an indigenous species which 

 has become unusually numerous owing to the development 

 of orchards, or whether it is introduced, has not yet been 

 ascertained. In 1905, when this insect was exceedingly 

 numerous, the pear-crops were hopelessly blighted, but 

 how much of the injury was due to the thrips and how 

 much to wet weather is uncertain. Owing to the long 

 period spent by the thrips underground, remedial measures 

 are difficult to apply. Practically the whole of the eastern 

 half of the United States is infested by the chinch-bug, 



