i7ijurious to Vineyards. 487 



sides of the bell-glass, where it instantly perishes by asphyxia. 

 Two hundred of these lights were established in a part of the 

 vineyard of M. Delahante, about four acres in extent, and at a 

 distance of 25 ft. from each other. These fires last about two 

 hours ; and scarcely had they been lighted, when a great number 

 of moths came flying around, and were speedily destroyed by 

 the oil. The next day the deaths were counted. Each of the 

 200 vessels contained, on an average, 150 moths. This sum, 

 multiplied by the first number, gives a total of 30,000 moths 

 destroyed. Of these 30,000 insects, we may reckon one fifth 

 females, having the abdomen full of eggs, which would speedily 

 have laid, on an average, 150 eggs each. This last number, 

 multiplied by the fifth of 30,000, that is to say, by 6000, would 

 give for the final result of this first destruction the sum of 900,000. 

 On the 7th of August, 180 lamps were lighted in the same place, 

 each of which on an average destroyed 80 moths, or a total of 

 14,400. In these 14,400 moths there was reckoned to be, 

 not only one sixth, but three fourths, females : but, admitting 

 that there was only one half females, or 7200 ; and, multiplying 

 this by 150 (the number of eggs that each would have laid), 

 gives a total of 1,080,000 eggs destroyed. Two other experi- 

 ments were made on the 8th and 10th of August, which 

 caused the destruction of 9260 moths. 



The expense attending this process is a very great objection ; 

 but M. Audouin had recourse to a less expensive mode, namely, 

 that of hand labour. These moths, as already observed, lay 

 their eggs in clusters of about 150 each, on the upper side of 

 the vine leaves. Each cluster contains a greater or less number 

 of eggs ; but 60 may be taken as the average. It is these eggs 

 which give birth to the devastating insects. If the eggs were 

 destroyed, the source of the evil would be totally arrested. On 

 the 7th of August, 20 vine-dressers, women and children, were 

 set to work, under the direction of M. Audouin, in the vineyard 

 of M. Delahante ; and this operation was continued till August 

 11. inclusive. The following is the result obtained : — 186,900 

 clusters of eggs were collected, which was equal to the destruc- 

 tion of 11,214,000 eggs. This operation was continued from 

 the 12th of August to the 18th of August, by thirty persons, 

 during which time 482,000 clusters of eggs were gathered ; 

 which, multiplied by 60 (the average number in each cluster), 

 gives 28,920,000. Thus, in twelve days, from 20 to 30 workers 

 destroyed 40,182,000, which would have been hatched in the 

 course of from 12 to 15 days. 



M. Audouin related several other experiments of the same 

 kind which had been tried in various places. He thinks that 

 collecting the eggs is superior to any other mode that has been 

 proposed or put in practice; and, if used conjointly with the 



1 1 4 



