Report of the Researches of M. Ar/assiz, 293 



most compact ice, sometimes at the depth of two or three 

 inches. 



The phenomena of infiltration were, of all our experi- 

 ments, the ones which most interested travellers ; and hence 

 all our friends who took an interest in our researches were 

 too happy to examine them. The gallery itself present- 

 ed a curious spectacle, and involuntarily suggested to the 

 mind some crystal grotto of the fairies, surrounded as it was 

 by subterranean and yet resplendent walls. For a time, all 

 our observations were made under the influence of the light of 

 day. We were desirous of likewise observing how the coloured 

 liquid would appear during the darkness of night, and M. Agas- 

 siz, accompanied by M. Escher de la Linth, visited the gallery 

 after nightfall on the 1st of August. About 9 p.m. they poured 

 two quarts of the infusion into the hole, and as it was then ex- 

 ceedingly cold (the thermometer indicating — 0°. 6, or 30°. 9 F.), 

 they scarcely hoped for a satisfactory result. They imagined 

 that the infusion would congeal before it could penetrate far ; 

 and therefore, were all the more agreeably surprised to per- 

 ceive the coloured liquid on the roof of the gallery in five mi- 

 nutes. Thus, it was demonstrated that the external cold did 

 not hinder the infusion from circulating in the capillary fis- 

 sures, since it penetrated with more velocity than during the 

 heat of the day. Hence, since the nocturnal cold did not sen- 

 sibly influence the temperature of the ice, it was easy to ex- 

 plain the accelerated movement of the liquid during the night ; 

 for this simple reason, that as the fissures received less of the 

 surface-waters for several hours, they became empty, and con- 

 sequently the passage of the infusion was facilitated. The 

 glacier might thus be compared to a sponge from which we 

 have squeezed out the w^ater, and which, of course, is all the 

 more ready to receive more. The fissures, themselves, are 

 also much more distinct during the night, and, with the light 

 of a candle, rather than with that of day. In these circum- 

 stances, they can be traced in the walls of the gallery to a 

 depth of about three feet. A light placed in the gallery could 

 be seen very distinctly through the opposite wall, through a 

 thickness amounting to eight feet and more. 



From this fact, an important deduction follows, namely, that 



