I40 



NA TURE 



[April i, 1909 



and March numbers of the Bulletin de la Society astro- 

 nomiqne de France. The results are founded on the 

 observations made at the Juvisy Observatory, and deal with 

 temperature, pressure, rainfall, insolation, cloudiness, &c. 

 Numerous curves show the daily or monthly march of each 

 element, whilst other curves and tables compare the results 

 Avith those of previous years since 1886. Comparisons are 

 also made of the seasons, and those having similar 

 mcteorolog-ical records in different years are grouped 

 together in a very handy form for reference. In a general 

 remark, the observers state that for several years now late 

 summers have been the rule. 



The director of the meteorological observatory, 

 Chemulpo, has sent us the results of the observations made 

 at six Japanese meteorological stations in Korea for each 

 of the months January-December, 1907. The observations 

 are made thrice daily, with monthly summaries, and are 

 a valuable contribution to the meteorology of the Far 

 East. .\n annual summary would be a very useful addi- 

 tion to the tables, which have been very carefully prepared 

 by Mr. Y. Wada. The instruments and method of observa- 

 tion are the same as those at the meteorological stations 

 in Japan ; this is a sufficient guarantee of their accuracy. 



The fifteenth annual report of meteorology in Mysore, for 

 1907, has been received, containing daily and monthly 

 means for the second-class stations of Bangalore and 

 Mysore, and 8h. a.m. observations and means for the third- 

 class stations of Hassan and Chitaldrug. The altitude of 

 ithese important stations varies from approximately 2400 

 feet at Chitaldrug to 3100 feet at Hassan, and they lie at 

 ithe corners of a quadrilateral of which the diagonal, 

 ninety-seven miles in length, is almost due west, Bangalore, 

 the easternmost station, being 190 miles west of Madras. 

 The observations have been very carefully discussed by 

 Mr. N. V. Iyengar, chief observer in charge, and include 

 mean values for the years 1893-1907. The absolute 

 maxima of shade temperature during that period exceeded 

 100° at all stations, and reached 103° at Chitaldrug ; the 

 lowest reading was ■\2°-y, at Hassan. On extreme 

 occasions relative humidity fell to between 4 per cent, and 

 6 per cent, at the different stations. The mean yearly 

 rainfall varied from 25-6 inches at Chitaldrug to 35 inches 

 at Bangalore. 



A CORRESPONDENT, Mr. A. E. H. Bott, of Fishburn, 

 Alberta, asks for information on a matter which is of 

 'Common interest to many where severe cold is experienced. 

 An ordinary horizontal minimum thermometer filled with 

 coloured alcohol was placed about 6 feet above the ground 

 on the north wall of a house. The instrument registered 

 :from —60° F. to 4-114°. In the early part of January 

 the thermometer registered from —35° to —53° for about 

 six or seven nights in succession. The thermometer was 

 tilted every day in order to replace the index at the end 

 of the thread of alcohol. The thermometer was afterwards 

 left untouched for some days, while the observer was away 

 from home, and it was then found that the colouring 

 matter, apparently the red of cochineal, had entirely left 

 the upper part of the thread, which w'as now difficult to 

 see. When writing, the top of the column stood at 4- 14°, 

 but the deep-red colour began to pale at about —50°, and 

 faded gradually until it disappeared completely at about 

 — 14°. It seems probable that the cochineal was frozen 

 out of the solution, and that the mixture was rather 

 mechanical than chemical. In all probability heating or 

 warming the mixture would restore the instrument to the 

 same condition as when purchased, but a recurrence of 

 'the separation of the colouring matter with extreme cold 

 ■seems probable. 



NO. 2057, VOL. 80]* 



In the Bulletin of the American Mathematical Society 

 for March, Miss Eva M. Smith discusses some surfaces 

 having a family of helices as one set of lines of curvature. 

 From the investigation it appears that surfaces can exist 

 one set of the lines of curvature of which are general 

 helices defined by constant ratio of curvature and torsion, 

 but no surfaces have regular helices (i.e. helices on right 

 circular cylinders) for their lines of curvature. 



The February issue of the Journal of the Institution of 

 Electrical Engineers contains Mr. W. R. Cooper's paper 

 on the tariffs now in force for the supply of electricity for 

 domestic purposes. He considers that their present 

 tendency is to discourage the demand for electricity, and 

 advocates with much force the substitution for them of the 

 payment of a fixed sum per annum based on the number 

 and power of the lamps installed, plus a small charge, not 

 exceeding one penny per unit, for the electricity used. In 

 the discussions of Mr. Cooper's paper, which took place 

 in London, Glasgow, and Dublin, widely divergent opinions 

 were expressed by lighting engineers as to the relative 

 merits of the old and the proposed systems, but almost all 

 were agreed that some reform is necessary if the more 

 extensive use of electricity for domestic purposes is to be 

 encouraged. 



Metallurgists who have not made a special study of 

 the accurate measurement of high temperatures, and who 

 are therefore not in a position to judge of the relative 

 merits of the various determinations of the melting point 

 of iron, will be very grateful to Prof. Carpenter, of Man- 

 chester, for a critical summary of our knowledge on the 

 subject, which appears in part iii. of the Journal of the 

 Iron and Steel Institute for 190S. After a brief statement 

 of the relations of the gas, the thermo-electric and the 

 optical temperature scales to each other. Prof. Carpenter 

 gives the results obtained during the last five years by 

 observers at the national physical laboratories of Germany, 

 France, America, and England, and concludes that the 

 freezing point of iron is 1505° C. on the thermo-electric 

 temperature scale, which corresponds to 1519° C. on the 

 optical scale as at present used. 



We have received eight pamphlets forming appendices 

 to the annual reports of the Coast and Geodetic Survey 

 from 1899 to 1906, which deal with the observational mag- 

 netic work carried out in the United States under the 

 supervision of Dr. L. A. Bauer, chief of the division of 

 terrestrial magnetism. These appendices consist largely of 

 observational data, accompanied by descriptions of the 

 stations where the observations were made. Particular 

 care is taken in indicating the exact sites, which are 

 marked with wooden pegs or stone blocks. In addition to 

 observational details there are descriptions of the magnetic 

 observatories of the Survey and their instrumental outfit, 

 as well as of the field instruments. The instruments at 

 the fixed observatories seem mainly of German origin. Of 

 the field instruments, the magnetometers are of a special 

 pattern — a combined magnetometer and theodolite — made 

 in the Survey's workshops. The dip circles — including the 

 ordinary land pattern and the Lloyd-Creak for use at sea — 

 are mostly of English make. Fitted with Lloyd's total- 

 force needles and an auxiliary compass, the dip-circle seems 

 to have proved a very useful universal instrument. The 

 latest of the publications contains an isogonic chart for 

 the United States for the epoch 1905, based on results 

 from some 3500 stations, and it also gives tables of secular 

 change — a good many extending back to 1750 — for some 

 eighty stations. Lists of observers in several years include 

 more than thirty names, and it is abundantly clear that 



