322 



NATURE 



[November i8, 1915 



deficiency from the average nowhere amounted to i°, 

 and was generally only a few tenths of a degree. 

 Bright sunshine was generally slightly in excess of 

 the average in the western districts, and there was a 

 slight deficiency in the eastern districts. 



The report on the Survey of India for 1913-14 

 records much useful work. The new topographical 

 survey makes steady progress. More than 300,000 

 square miles have been done since 1905, but about half 

 a million remain to be done. About one-sixth of the 

 total number of one-inch sheets of the map of India 

 are now published, and a half-inch map is proposed. 

 Of the quarter-inch map some new sheets were pub- 

 lished, making a total of 18 out of 450. Most of the 

 sheets of India, Afghanistan, and Baluchistan on the 

 one-millionth scale are ready. Layer colouring has 

 been adopted for the more recent ones. The scale of 

 tints is still to be the subject of experiment. Several 

 sheets of the international one-millionth with the Paris 

 colour scheme are in preparation. During the year 

 three sheets of Afghanistan, Baluchistan, and Northern 

 Persia on a scale of i to 2,000,000 were published. 

 The sheet of southern Persia previously appeared. 

 Others of IndTa on this scale are in preparation. 



Hyorographical investigations in Faroe waters 

 form the subject of a paper by J. P. Jacobsen in 

 Meddelelser jra Kommissionen fer Havunders(/>gelser 

 (Bind ii., Nr. 4, 1915). In Trangisvaag Fjord, where 

 most of the work was done, it was found that the 

 water-level changed with the barometer, but that the 

 influence of prevailing winds was extremely slight. A 

 fourteen-day period of change was also observed. In- 

 vestigations on the currents of the waters between 

 the Faroes and Shetland bear out Nansen's previous 

 discoveries, that the north-going current along the 

 Shetlands is strongest where the depth is between 

 150 and 200 metres. The same is the case with the 

 south-going current along the eastern side of the 

 Faroe plateau. The lower surface temperature and 

 salinity over banks than in adjacent waters in the 

 north-east Atlantic has more than once been noted. 

 This phenomenon Mr. Jacobsen believes he has traced 

 to the greater mixing of the upper and lower water on 

 the bariks than elsewhere, due largely to strong tidal 

 currents. In deeper places the mixing was far less 

 pronounced. 



Prof. Ignazio Galli, whose notes on lightning we 

 have had occasion from time to time to cite, recently 

 published an account of a lightning stroke which fell 

 on January 25, 1915, in Rome, upon the Church of 

 San Gioacchino in Selci. He himself witnessed from 

 a distant house a brilliant light of an orange colour 

 and heard a single sudden explosion. He believed it 

 to be a case of globe lightning. Subsequent inquiry 

 of witnesses in the neighbourhood confirmed him in 

 the opinion ; they described the appearance as a red 

 or reddish globe, 40 to 45 centimetres in diameter, 

 which, moving over the roofs from north towards 

 south, struck the cross of the church with a blinding 

 light and a deafening crash. It is singular that Prof. 

 Mengarini, of Rome, when a student at the Technical 

 NO. 2403, VOL. q6] 



Institute, near San Pietro in Vincoli, witnessed a 

 similar lightning stroke fall on the same church on 

 February 28, 1876. 



Circular No. 38 of the Bureau of Standards, Wash- 

 ington, a third edition of which has recently been 

 issued, deals with the subject of testing india-rubber 

 goods. Both physical and chemical methods of test- 

 ing are included in the descriptions. It is pointed out 

 that the constantly increasing demand for rubber 

 goods by the general public, by railway companies, 

 and other large consumers, indicates the necessity for 

 developing standard specifications and tests for rubber, 

 as has been done in the case of iron and other mate- 

 rials. In connection with the chemical tests, explana- 

 tions are given showing the significance of certain 

 determinations and the reasons for making them. 

 This is done, for example, as regards the acetone 

 extract, the sulphur, the waxes, and the extracts 

 obtained with chloroform and with alcoholic potash; 

 the idea being to enable a person who knows but little 

 of rubber chemistry to understand the import of these 

 analytical data. The operations as carried out by 

 the bureau are set out in some detail, and, in addition, 

 a specification and suggested method of analysis for 

 rubber insulation compounds adopted by the Joint 

 Rubber Insulation Committee are included for general 

 information, though not officially endorsed by the 

 bureau. Those interested in the subject may find it 

 useful to consult the circular, which is a convenient 

 epitome of the usual tests. 



To meet modern conditions governing condensation 

 of steam in power plants, it has become usual to ex- 

 tract the air and water from the condenser by inde- 

 pendent means. High-speed centrifugal pumps provide 

 very effective means of removing the condensate, and 

 various forms of steam and water-jets, or pumps, are 

 in use for the removal of the air. An interesting- 

 example of one of these new forms of air pumps — 

 on the Williams-Miiller system — is described in 

 Engineering for November 12, The system is applied 

 to a condenser for a 8500-kw. turbine at the Sheffield 

 Corporation power station. This condenser is to give 

 a vacuum of 285 in. at full-load output when supplied 

 with circulating water at 62° F. The jet-pump is in 

 principle identical with the common filter-pump used 

 in laboratories, but much experiment has been neces- 

 sary in order to determine the most suitable arrange- 

 ment and proportions. In a trial of one installed at 

 Glasgow, it was found that, starting with the con- 

 denser full of air at atmospheric pressure, a vacuum of 

 20 in. was attained in 25 minutes, and 29 in. in 

 8 minutes. 



The annual report of Lloyd's Register for 1914-15 

 was published recently, and it is interesting to note 

 that, in spite of losses owing to the war, the tonnage 

 classed with Lloyd's for the year ending June 30 last 

 was 300,000 tons in excess of that classed for the 

 previous year. More than 300 vessels have been 

 built, or are being constructed, on the Isherwood 

 system of longitudinal framing; the tonnage of these 

 vessels amounts to 1,675,000 tons gross. There are 

 290 vessels now classed for the carrying of petroleum 



