July 13, 



1893] 



NATURE 



251 



NOTES. 



TlIL annual meeting of the Institution of Naval Architects 

 commenced at Cardiff on Tuesday, when an important paper 

 upon "Fast Ocean Steamships" was read by Dr. Elgar. 

 Owing to the rough weather, Lord Brassey, the president, was 

 unable to be present, his yacht being prevented from reaching 

 the fort. 



The forty-second meeting of the American Association for 

 the Advancement of Science will be held during August at 

 Madison, Wisconsin. The local secretary is Prof. C. R. 

 Barnes, of the State University. 



The second annual meeting of the International Union of 

 Photography will be held in Geneva from August 21 to 26. The 

 headquarters of the Union are at 33, Rue Rembrandt, Antwerp. 



Arrangements have been made for a visit of the Geologists' 

 Association to Ireland from July 24 to 29. The directors of 

 the excursion are Profs. W. J, Sollas, F.R.S., and Grenville 

 A. J. Cole, and a very attractive programme has been provided. 

 In addition to the serious work, more than one social gathering 

 is promised, so the trip will doubtless be enjoyed by all who 

 undertake it. A geological map of the district to be visited, 

 prepared by Prof. Cole, is printed in the special circular 

 'ssued for the excursion by the Association, and Piof. Sollas's 

 paper on the geology of Dublin and its neighbourhood, 

 read before the Association on the 7th inst., is now in the press, 

 and will be published the day before the party leaves London. 

 As it is important to obtain an early estimate of the probable 

 number of the parly, all members who propose joining the ex- 

 cursion should apply at once to the Secretary, Mr. Thos. 

 Leighton, Lindisfarne, St. Julian's Farm Road, West Norwood, 

 S.E. 



A COPY of the report of the Zoological Society that has just 

 been printed has been received. Its contents will be sum- 

 marised next week. 



The fifth Congress of Arcb.xological Societies in union with 

 the Society of Antiquaries was held on Tuesday at Burlington 

 House, Sir John Evans, K.C.B., F.R.S., being in the chair. 

 About forty delegates were present, including Lord Hawkes- 

 bury, Mr. Stanley Leighton, M.P., Profs. Flinders Pelrie, and 

 E. C. Clark, &c. It was announced that progress had been 

 made with ihearchiEological maps of Essex, Derbyshire, Sussex, 

 and Surrey. Several papers were read, one on "A Photo- 

 graphic Record of Archreological Objects " exciting an interest- 

 ing discussion. 



The Laboratory of the Marine Biological Association at 

 Plymouth ha> still a few tables unoccupied for the summer 

 vacation. Applications for permission to work there should 

 be sent in without delay to the Director. 



Writing from Murree, on June 7, Mr. F. C. Constable says 

 that, during a recent hailstorm, corrugated iron roofs were in 

 many cases perforated by the hail. He measured one hailstone 

 four hours after the storm, and found it to be 4J inches 

 round. 



A VIOLENT thunderstorm occurred on Ben Nevis last week 

 from II p.m. of Friday to 2 a.m. of Saturday, St. Elmo's fire 

 .ipptating there at the same time. During another thunder- 



irm on Saturday afternoon flashes came off from the telegraph 

 .i:re connections inside the observatory; and about the same 

 time a fire-ball was seen to strike the ground near the foot of 

 the hill. The hygrometric fluctuations at the time were re- 

 markable. 



MO. 1237, VOL. 48] 



During the past week sharp thunderstorms have occurred in 

 many partsof the British Islands, accompanied by hail and very 

 heavy rain. Between the 7.h and 9th the fall within twenty- 

 four hours exceeded an inch at several places in the north of 

 England and in parts of Scotland, and in the north of Ireland 

 on Sunday it amounted to 281 inches, a fall more than double 

 the total for the month of June this year. The temperature 

 was also exceptionally high in the southern parts of England 

 during the first part of the period, the maximum reading being 

 89'''9 at Greenwich on Friday and Saturday, a temperature 

 which was not equalled in any part of the summer during the 

 five years 1888-92, and at Cambridge the shade reading on 

 Saturday registered 92°. 



Since February, 1892, a Richard thermograph has been in- 

 stalled on the summit of the Obir, at a height of 2140m., or 

 about looom. below the level of the Sonnblick Observatory. 

 The records of temperature up to February, 1893, as shown 

 by this thermograph, were communicated and discussed by 

 Director J. Hann at a recent meeting of the Vienna Academy 

 (June 12). They afford a valuable contribution to the 

 knowledge of the daily changes of temperature in the higher 

 regions of the atmosphere. A comparison with the cor- 

 responding temperatures registered on the Sonnbjick shows an 

 almo-t identical course of changes, except that in summer the 

 range on the Obir was perceptibly larger. During eight 

 months, from October to May, hardly any daily variation is re- 

 corded in the decrease of temperature with height between the 

 Obir and Sonnblick. In the summer months, the most rapid 

 decrease was found to occur at I p.m., being o°'74 per loo.n., 

 he least rapid at II p.m., being o''6i per loo.n. Ttie mean 

 decrease per loom, for the summer months was o°'67, for winter 

 o°'54, and for spring and autumn o°'56. 



A NEW determination of the mass and the density of the 

 earth has been made by M. Alphonse Berget, who describes his 

 method in the current number of the Comptes Kcndns. It con- 

 sisted in altering the level of a lake by i m., and noticing the 

 effect produced upon a hydrogen gravimeter such as was used 

 by Boussingault and Mascart to determine the diurnal variation 

 of gravity. The lake was that of Habaz-la-Neuve, in Luxem- 

 burg, of 79 acres area, belonging to M. Fran9ois de Curel. 

 The level could be raised or lowered in a few hours. The vari- 

 ation of the column of mercury was minutely observed by 

 means of Fizeau's interference fringes, produced in vacuo be- 

 tween the surface of the mercury and a piece of plane-polished 

 glass at the bottom of the observing tube. Two series of read- 

 ings were taken, the one on lowering the level of the lake by 

 50 cm. and I m., the other on raising it by the two correspond- 

 ing amounts. The displacement of the column for a change 

 of level of I m. was i 26 x 10" cm. The value for K, [the 

 constant of gravitation, i.(. the attraction in dynes produced by 

 a mass of l gr. upon another placed i cm. from it in air, was 

 found to be 680 ;■ lo*. The mass of the earth was found to be 

 585X10-' grammes, and its density 5'4(, which is in fair 

 agreement with results hitherto obtained. 



During the cruise of the Blanche in the neighbourhood of 

 Jan Mayen and Spitzbergen, M. G. Pouchet made some inter- 

 esting observations of the various kinds of ice to be found on 

 those barren Arctic islands. In the northern lagoon of Jan 

 Mayen, which was partly covered with ice on July 27, 

 the ice, according to a description in the Comptes RenJui, was 

 formed of irregular vertical prisms about 10 mm. thick separated^ 

 by spaces of about l mm. and joined at the upper surface by 

 a uniform layer of semi-transparent ice i to 2 mm. thick. At 



