498 



NA TURE 



[September 13, 1906 



of this system. Some of the large electrical manufacturing 

 firms have entered actively into the development and supply 

 of machinery in this new field, and some striking illustra- 

 tions are given by Mr, Franz Koester in the Engineering 

 Magazine (vol. xxxi., No. 5) showing views taken on farms 

 where electricity is used exclusively for motive power. 



In the Revue de Mitallurgie (vol. iii., No. 2), issued as 

 a supplement to the Bulletin de la Sociite d'Encoiirage- 

 ment, Mr. Guillery describes a new method of determining 

 the elastic limit of metals by recording the variations in 

 the electric resistance of the test-piece as the load in the 

 testing machine is increased. The method is not yet fully 

 developed, but the results of a number of tests made by 

 the author at Denain, and the simplicity of the apparatus 

 used, render it worthy of careful consideration. 



In the case of an engine using saturated steam, the 

 PV diagram can be converted into the 6tt> equivalent either 

 by a somewhat tedious calculative method or by Boulvin's 

 graphic method. The latter necessitates the preliminary 

 re-plotting of the diagrams to the pressure and volume 

 scales before the graphic transference can be carried out. 

 .'\ modification of this method has been devised by Mr. 

 W. J. Goudie, and is described in the Engineering Reviezv 

 (vol. XV., No. 2). A direct transference from the actual 

 indicator diagrams is effected, and the saving in time and 

 labour should render the method useful to engineers who 

 make frequent use of the temperature-entropy chart. 



The September issue of the new bi-monthly journal 

 Concrete contains admirably illustrated articles on the 

 micro-structure of Portland cement by Dr. C. H. Desch, 

 and on reinforced concrete at the Milan Exhibition by Mr. 

 F. R. Farrow. This new addition to technical periodical 

 literature should prove a valuable source of information to 

 all workers in concrete and. cement. The details of the 

 new uses to which concrete and reinforced concrete are 

 put are very remarkable. The use of reinforced concrete 

 as a substitute for timber in exposed positions is rapidly 

 increasing. Railway sleepers, telegraph posts, and fence 

 posts are being tried, and efforts are being made to prove 

 that reinforced concrete is an excellent substitute for brick- 

 work where structures of great height are required. 



We have received from the Geological Survey of Canada 

 three reports of special economic interest. The report 

 fNo. 923) on the Chibougamau mining region in the 

 northern part of the province of Quebec, by Mr. A. P. 

 Low, records the discovery of an area of serpentine rocks 

 containing asbestos of excellent quality, together with the 

 finding of a large vein of gold-bearing quartz and numerous 

 indications of copper ores. Mr. R. W. Brock submits a 

 preliminary report (No. 939) on the Rossland mining dis- 

 trict, British Columbia. A more complete report is in pre- 

 paration. Mr. C. W. Willimott's monograph on the 

 mineral pigments of Canada (No. 913) contains the results 

 of an elaborate series of experiments with the various pig- 

 ments that can be derived from minerals, ochres, and clays 

 either in their crude state or by burning. They show that 

 in almost every colour a paint of good body and permanent 

 tone may be produced from Canadian material. 



An account of Sinhalese earthenware is given by Mr. 

 A. K. Coomaraswamy in vol. iv., part xiii., of Spolia 

 Zeylanica. Elaborate types are not found, and no glaze is 

 used ; the sides of the pots are made on the wheel, which 

 is turned by a boy ; some hours or days later, putting a 

 smooth stone inside, the potter fashions the lower part 

 of the sides so as to form the bottom — a most unusual 

 procedure. In addition to domestic and ritual pottery, the 

 NO. 1924, VOL. 74] 



author deals with roof-tiles, some of which, for use on the 

 eaves, are decorated. Earthen vessels are also decorated 

 with incised, stamped, or slip-painted designs, and the 

 most effective of these styles is stamping, though some of 

 the incised designs produce a very Greek-like effect. The 

 paper is illustrated by three collotypes and numerous blocks 

 in the text. 



The summary of the weather for the week ended 

 September 8, issued by the Meteorological Office, shows 

 that the highest shade temperature in the recent hot spell 

 was 96°, at Bawtry, in the Midland counties, registered on 

 September 2. The rains which occurred with the change 

 to cooler weather were very heavy in places, although by 

 no means general. In parts of London the fall on the 

 night of September 4-5 amounted to an inch, and to i'68 

 inches at Ventnor ; while at Glencarron the measurement 

 on September 5 was 1-98 inches, and at Fort William 

 i'87 inches. In most parts of England the weather has 

 been exceptionally dry for nearly three weeks. .At Spurn 

 Head and Bath no rain has fallen since August 24, and at 

 Shields none has fallen since August 26, while at many 

 places, widely separated, the measurement since about 

 August 25 amounts only to a few hundredths of an inch. 

 The general type of weather which has characterised the 

 summer is still continuing. Bright sunshine is unusually 

 prevalent, with very dry conditions, but the temperature 

 has fallen, although the days at present are still mostly 

 warm. At Greenwich, the exposed thermometer on the 

 grass registered 28° on the morning of September 11, and 

 the ground in the suburbs of London was coated with hoar- 

 frost. 



We have received from the meteorological reporter to 

 the Government of India a memorandum on the weather 

 conditions during June and July, with an estimate of the 

 monsoon rainfall during .August and September, 1906. It 

 is stated that the total rainfall of June and July was dis- 

 tributed with about the usual uniformity over the greater 

 part of India; the only areas of large defect were Sind 

 (52 per cent.), the Punjab (27 per cent.), and Bengal (21 per 

 cent.). In both these months there was, on the average 

 of the whole country, a defect of 3 per cent, in the rain- 

 fall. In forming a forecast for August and September, the 

 conditions in various parts of the world are stated ; of 

 these, the most powerful factor is thought to be the 

 pressure in the southern Indian Ocean. An illustration of 

 this is given by a table containing all years since 1875 in 

 which pressure at Mauritius in July differed from the 

 normal by more than 0024 inch, together with the rain- 

 fall of Bombay and bay currents in the ensuing August 

 and September ; it shows that there is a marked tendency 

 for high pressure to be followed by deficient rainfall, and 

 vice versd. At Mauritius, pressure this year was below 

 the normal in June by 0045 inch, and in July by 0-020 inch, 

 a fact which is, therefore, decidedly favourable ; but so 

 many factors come into play, e.g. temperature, the dis- 

 tribution of snowfall in the mountain regions north and 

 west of India, and probably pressure over South America, 

 that Dr. Walker is unable to say more than that there 

 appears, on the whole, to be no reason for anticipating 

 either a large excess or a large defect in the rainfall of 

 August or September. 



The Royal Society of Canada, which was founded by the 

 Duke of Argyll in 188 1, celebrated its semi-jubilee this 

 summer. The president. Prof. Alexander Johnson, in his 

 address at the annual meeting, described the conditions 

 which led to the society's inception and the development of 

 its activities. A large portion of the address was appro- 



