46 



ATMOSPHERIC ACTINOMETRY 



hanging in a noitliein exposure, against the wall of a house with loft}- arcades, and 

 consequently untl»-i- a gallery formed by them. In the statements concerning the 

 winds, the freijuent violent changes of whicli we spoke at the be<;innin"' will be 

 noticed. 



When M. Gessard sent me the reports for August and Septem1)er, he added 

 wliat follows: "They seem to me to conlirui the fiinner. The c-oml)Ustions have 

 not been more intense than in .luly. 1 notice, on the other hand, that during over- 

 cast weather they have not l>een inl'fiior to those observed on days of full sunshine. 

 The second fact which stiikes me is lliis : that the quality of combustion should 

 be maintained with such constancy in the two vessels under all circumstances. 

 Tlius, on the 11th September (T did not report it in the table), with a south wind 

 blowing all day, raising the niaxiniuni temperature to 32° 4', the contents of both 

 vessels having evaporated, although tlu-y had iteeti allowed to float u|)on the water, 

 I had the curiosity to re-dis.solve the residual acid and to test it : I found 8.4 c. c. 



