J WI'AKY 30, 1919] 



NATURE 



43 1 



I in ( ambrldgi Scientifii [nstrumenl Co., Ltd., has 

 issued .1 leaflet describing typical instruments for use 

 in power stations. B) means oi a large diagram the 

 company illustrates when some of its instruments can 

 bi usefully placed in the boiler-house, dynamo station, 



ngini a '- room. B) the use of an electric distani 1 

 thermometer the engineer can at once tell the tem- 

 perature of tin- steam at the stop-valve, ol thi cir- 

 culating water al the inlei and outlet, and also of the 

 supply air, condenser, and oil at their inlets and out- 

 lets. This leaflet will help the engineer to understand 

 how useful electrical distance thermometers can be. 

 These thermometers can be placed in almost inac- 

 cessible positions, such as the base ol a smoke-stack 

 or in and economisers. Hepce the neces- 



sity For men having to climb la . at frequent 



intervals ran be obviated. There will also be a great 

 saving ol labour in recording the wet- and dry-bulb 

 temperatures in cooling-towers. The leaflet shows 

 an illustration of a distance thermometer recorder 

 fixed on the table in the engineer's room. In the 

 boiler-house it also shows the company's well-known 

 dial draught gauge and its bi-meter CO, recorder. As 

 it seems certain that in the near future many huge 

 power stations will be constructed in this 

 country, there will he a great demand lor all kinds ol 

 Scientific measuring instruments. The usual custom 

 of placing contractors under monej penalties - for 

 failure to comply with the steam efficiencj guaranteed 

 in the specification is an excellent one. In many cases 

 the lost of the most elaborate thermal tests is but a 

 small fraction of the money penalty at stake. Hence 

 thi accuracy of these tests has been much improved 

 ..I recent \' 



Mr. C. M. vVhittaker wrote some time ag 



object to some statements made bv the reviewer of 

 his 'Modern Dyeing Methods" in our issue of 

 November 7 last. Reference was made in the review 

 to inadequacy of treatment of one section of the book/ 

 to lack of proportion in another, and to the omission 

 of exact quantitative methods of estimating dyestuffs. 

 It is obvious that upon these matters a reviewer is 

 justified in expressing his .opinion, even though it 



not coincide with that of the author; and also 

 that no useful scientific purpose would be served by 

 the publication of correspondence upon the different 

 points of view, even if space permitted of it. On one 

 matter, however, we are glad to correct a statement 

 in the review. Though the sections on direct cotton 

 dyestuffs, the insoluble azo-colours, and the resorcine 

 dy( stuffs do not give lists of groups at the beginning, 

 as in earlier sections, the examples are included else- 

 where in the sections, and our reviewer regrets that 

 he overlooked them. 



Tin .si interested in the mechanical handling of 

 materials will find a great deal of useful information 

 and applications in the Electrician for January 10. 

 Vmong "tli, 1 subjects treated in this special number 

 is that of the gravity conveyor. On this principle 

 it is win ih while to elevate the materials sufficiently 

 at one stage of the process so that their progress 

 thereaftei is obtained automatically by gravity. Con- 

 on this svstcm have been in existence for many 

 for example, in flour mills- hut the application 

 has been extended greatly during recent years. The 



nt of a gravity installation varies from 

 t per cent.; the latter figure is not the 

 maximum, but it is rarely insufficient. The 

 " humper " is used when it is desired to convey for a 

 distance longei than that obtainable by the available 

 head 01 fall, and consists of a short mi 1 hanical elevator, 

 generally inclined at 45 . which renews the gradient 

 and thus permits the packages to travel to the end of 

 the runway. Roller paths, switches, curves, shoots, 



NO. 2570, VOL. I02] 



and other accessories are described fully in the article. 

 Another section of the journal of interest to engineers 

 is- an article on conveyor chains, sprocket-wheels, 

 buckets, etc. This is fully illustrated with 



di tail drawings. Then Iso vei ) full artii les on 



the pneumatic handling ol cereals, the equipment of 

 silo granaries, and munition-handling devices, which 

 cannot fail to be of service to any desirous ol obtaining 

 information regarding these laboi r-saving appliances. 



The greatest departure in the * practice of ship- 

 building which has been recently introduced is the 

 extensive adoption of the " straight-frami " system of 



construction. This was begun and cat I out to a 

 very large extent by Sir Eustace d'Eyncourt and Mr. 

 Thomas Graham, who got out designs on System 



in the early summer of 1917. The idea of the design 

 is to build a ship the transverse sections of which 

 showed straight sides and bottom intersecting at a 

 point forming an angular bilge, but at the same time 

 retaining the orthodox shape of the waterplanes in a 

 fore-and-aft direction, so that the ultimate features 

 affecting resistance would not present anything likely 

 to demand an increase of driving power. Drawings 

 illustrative of this system appear in an article in 

 Engineering for January 17, and we learn from this 

 article that model experiments have confirmed the 

 contention of the designers, and that a suitable ad- 

 justment of the "chine" line at the ends would so 

 accommodate the form to the stream-line theory that 

 practically no extra power is required. The Govern- 

 ment adopted the type for its " National " (better 

 known as " N "-type) vessels. At present there are 

 built, building, and on order throughout the world on 

 the d'Eyncourt-Graham system vessels representing 

 750,000 to 1,000,000 tons of dead-weight. 



Messrs. Macmillan and Co.'s new list of announce- 

 ments contains many books likely to be of interest to 

 readers of Nature. Among them we notice "Annals 

 of the Philosophical Club of the Royal Society," written 

 from its minute-books by Prof. T. G. Bonney; 

 " Botany of the Living Plant," Prof. F. O. Bower, 

 illustrated; vol. ii. of "A Text-book of Embryology — 

 the Non-Mammalian Vertebrates," Prof. J. Graham 

 Kerr, illustrated; "Science and Fruit-growing," being 

 an account of the results obtained at the Woburn 

 Experimental Fruit Farm since its foundation in 1894, 

 the Duke of Bedford and S. Pickering; "Dr. John 

 Fothergill and his Friends : Chapters in Eighteenth- 

 century Life," Dr. R. H. Fox, illustrated; and a 

 new edition — the third — of Preston's "The Theory of 

 Heat," revised by J. R. Cotter, illustrated. Messrs. 

 Macmillan will also publish the following books by 

 American authors : — " Elements of Electrical Engineer- 

 ing," vol. i., " Direct- and Alternating-current Machines 

 and Systems," Prof. W. S. Franklin, and a second 

 edition of " Infection and Resistance," Prof. H. 

 Zinsser. Messrs. ]. M. Dent and Sons, Ltd., are 

 publishing "Osiers and Willows," by W. P. Elmore, 

 illustrated, dealing with their cultivation and use. 

 Messrs. P. S. King and Sou. Ltd., have nearly ready 

 for publication "The Silk Industry and Trade: A 

 Study of the Economic Organisation of the Export 

 Trade of Kashmir and Indian Silks, with Special 

 Reference to tlnir Utilisation in the British and 

 French Markets," R. C. Rawlley. Messrs. E. and S. 

 Livingstone (Edinburgh) will publish shortly vol. iii. 

 of Kraepelin's "Psychiatry" — "Dementia Precox" — 

 translated by Dr. R. Mary Barclay, and edited by 

 Dr. G. M. Robertson; also "Anatomy Mnemonics." 

 The Essex Field Club has in preparation a volume 

 by Miss G. Lister entitled "A Short History of the 

 siinK of Mycetozoa in Britain, with a List of the 

 Species recorded from Essex." It will be issued in 

 the club's series of special memoirs. 



