26 MOUNTAIN OBSERVATORIES IN AMERICA AND EUROPE. 



21 August — very heavy snow-storm ; a tourist and a guide are killed 

 by an avalanche ; 



22 August — violent storm ; 



23 August — snow-storm ; 



24 August — snow-storm ; 



25, 26, 27 August — the party goes to Chamounix for more work- 

 men; 



28 August — bad weather ; no work done ; 



29, 30 August — working; 



31 August — hurricane of snow ; no work ; 



1 September — fine day ; working ; 



2 September — working ; Dr. Jacottet dies on the summit ; 



3 September — descent to Chamounix. 



This, it must be remembered, is summer weather. The minimum 

 temperature on the summit of Mt. Blanc during the winter of 1894 was 

 _43°C= - 45°.4F. 



The cost of buildings at these heights is very great. Ordinary 

 laborers are paid 20 francs per diem when they are working near the 

 summit, and 15 francs at the lower stations. The price for transporting 

 one kilogramme to the summit is about 2.50 francs, or about 23 cents 

 per pound. The ordinary load for a porter is about 12 to 15 kilo- 

 grammes (26-33 pounds), though some of M. Janssen's men carried from 

 28-30 kilos. (62-73 pounds). It is reported that the work on the observa- 

 tories and stations built by M. Janssen has cost about $60,000, though 

 this figure may not be correct. The building of M. Vallot erected 

 in place cost about $9000, or about $74 per cubic metre. 



The weather during the summer of 1894 was very unfavorable on 

 the summit and the work was much interfered with. M. Janssen has 

 devised an instrument (showing the records of a mercurial barometer, 

 of the thermometer, hygrometer, and of the velocity and direction of 

 the wind,) which is self -registering, and which will run for several 

 months with one winding. This instrument is now ready for use. 

 The difficulty of thickening oil in the works is overcome, but it does 

 not appear how the traces of the different records (in ink ? pencil ?) 

 are to be made. Even the best pens, etc., require frequent attention, 

 especially at low temperatures. 



In notes printed in the Comptes Rendus of September 2 and October 

 7, 1895,* M. Janssen describes the work of the observatory during 

 1895. The first communication is dated August 31, and reports that 

 M. Bigourdan has determined the force of gravity at Chamounix and 

 at the Grands-Mulets (3050 metres). The determination at the sttm- 



* And in the Annuaire of the Bureau of Longitudes for 1896, p. D 1. 



