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GENEKAL AGRICULTURAL NOTES. [March 1896. 



GENERAL AGRICULTURAL NOTES. 



Experiments in Hatching Eggs. 



The French Ministry of Agriculture has given publicity to 

 an interesting article by Madame Dieudonne relating to the 

 effects of cold upon the incubation of eggs. 



A large number of fowls, some of which were kept in con- 

 finement and others allowed to run free, were kept under 

 observation day and night for a considerable period, and it 

 was noticed that the fowls, which were all good sitting hens, 

 hatched large and strong broods during the months of February, 

 March, and April ; but that during the warm months of June, 

 July, and August, the hatchings were not so successful, although 

 no change had been made either in the treatment and housing 

 of the hens or in their food. It was also found that the eggs 

 laid by hens in confinement, and collected every day and care- 

 fully stored, gave less satisfactory results than the eggs of 

 fowls which were at liberty. Madame Dieudonne inferred that 

 these difterences might be attributed to some extent to the 

 period of comparative cold which eggs generally undergo prior 

 to setting, and, as the result of further investigations and experi- 

 ments, she is of opinion that two conditions are necessary for 

 the successful artificial incubation of eggs, viz. : they must first 

 be cooled and then gradually warmed. 



This is indeed only an adaptation of what takes place in 

 nature, for fowLs on the farm hatch their eggs, and with remark- 

 able success, in hedges and out-of-the-way places where the eggs, 

 both before and during the period of incubation, are exposed to 

 considerable fluctuations of temperature, which not infrequently 

 falls below freezing point, and it is well known that partridges 

 almost invariably rear large broods in the early spring, unless 

 the eggs have been subjected to unduly bad weather. Cases 

 are also known of interrupted but successful hatchings when the 

 hens had left the nest even for several consecutive days. 



Moreover, Mme. Dieudonne has confirmed her opinion by ex- 

 perimental proof, and has always obtained excellent results with 

 eggs which had been placed in the open air during several 

 nights preceding the period of incubation, and artificially cooled 

 in the course of incubation, while when, on the contrary, this 

 process of cooling the eggs was neglected, good results were 

 never obtained. Her experiments showed that the eggs, after 

 having been completely cooled, slowly regained their normal tem- 

 perature, occupying seven or eight hours in the process ; the 

 chicks were strong and of rapid growth, but if the eggs regained 

 their normal temperature too quickly the chicks either died in 

 the shell, or they were born weak and anaemic and died within a 



