180 ASTRONOMY ON MONT BLANC. 



measuring 10 by 5 meters at the base might then weigh 200,000 kilo- 

 grams without being likely to sink in the snow more than a few 

 centimeters. If built on a rigid subbase and provided with jack- 

 screws, any strains which might arise by settling could be relieved, 

 and the whole could be leveled as it might require. In order to guard 

 against the fury of the storms it seemed desirable to make the 

 structure in the shape of a truncated pyramid and to bury the lower 

 part in the snow, so as to have a large and strong foundation. 



The object being approved b}^ M. Vaudremer, the eminent archi- 

 tect, member of I'Academie des Beaux-Arts, the construction was 

 commenced according to plans prepared under his direction. It com- 

 prised two stories, with a terrace and balcony. At the base the 

 pyramid measured 10 by 5 meters. The underground parts which 

 form the lower story are lighted by wide but low windows above the 

 snow. A spiral stairway communicates between the two stories and 

 the terrace, and extends above the latter to support a platform some 

 meters above, designed for meteorological observations. Double walls 

 protect the observers within from the cold, and the luiderground part 

 has a double floor separating it from the snow. The structure, 

 entirely of wood covered by canvas, was set up at Meudon and then 

 taken apart and transported to Chamonix. The total weight of the 

 materials exceeded 15 tons and made 700 or 800 loads for the porters. 

 As a precaution the route was divided into four sections, with stop- 

 ping places at the Grands Mulets (3,000 meters) and at Grand 

 Ilocher Rouge (4,500 meters). The first section, which comprised 

 the route from Chamonix to the foot of the glacier, allowed of the use 

 of the animals. In the second stage, ending at the public inn on the 

 Grands Mulets, there is nothing but glacier, and the materials could 

 only be transported on the backs of men. A shelter was constructed 

 at Grands Mulets to serve as a depot of supplies and refuge for the 

 porters. The trail from this station to the Rocher Rouge, which is 

 only about 300 meters below the summit, formed the third section, 

 and there was constructed here a hut for the carpenters and others 

 engaged on the work to pass the nights and take refuge in case of 

 bad storms. 



All the summer of 1892 was employed in the construction of the 

 observatory, its removal to Chamonix, and the partial completion of 

 the mountain transportation; and in the year 1893 all was up, at a 

 total cost of 40,000 francs. An accident just failed of ruining the 

 whole venture, for a depot of material, situated at Rocher Rouge, had 

 disappeared by spring, and was finally found buried beneath 8 or 9 

 meters of snow. 



For some months the great glacier of Mont Blanc, whose profile 

 stands like a gigantic staircase, appeared like a woodyard Avith its 



