192 ARTIFICIAL INCUBATION". 



wliich enclofses the chimney, up and down which it can move freely ; it 

 rises thus very nearly to its extremity. 



To preserve the moisture necessary for the health and development 

 of the chicks in the eggs, the boiler is surrounded by a double envelope 

 of copper, in the interval of which is poured a little water, Avhich by 

 its slow evaporation, gives the air the quantity of vapor necessary to its 

 temperature. 



The upper surface of the boiler can equally receive eggs placed upon 

 cotton during the incubation ; but when the chickens are hatched, we 

 take off the wadding and cover it with an oil-cloth, or make a cage of 

 it, where for a day we keep the young animals before feeding them. 



Under the platform of the fire is a coop, furnished with a sheep skin, 

 under which the chickens are warmly lodged till they can live in the 

 open air. 



The whole apparatus, which is square, octagonal, or better round, is 

 enclosed in a wooden case, in which there are a certain number of doors 

 or slides, to place and turn the eggs, and take out the chickens and per- 

 form all necessary operations. A certain number of very small tubes, at dif- 

 ferent heights, serve to supply the air necessary for the combustion as well 

 as to ventilate the interior. — Finally, some rather large openings, with 

 glass puttied in, enable us to see what is going on in the interior of the 

 apparatus, without the necessity of opening the sliding doors each time. 



Several other modes of hatching chickens have also been tried. Thus 

 advantage has been taken of the waste heat of the ovens of bakers and 

 pastry cooks, furnaces, steamboilers, and the like, where fire is constant- 

 ly employed, and which can be made to furnish a constant, uniform, 

 and very economical heat. This has also been done in simple cham- 

 bers, warmed with a portable furnace, and furnished with hooks, on 

 ■which the baskets of eggs are suspended, nearer or further from the fire, 

 according to the temperature. These chambers, however, need constant 

 attention, to be suitably regulated. 



Finally, M. D'Arcet, has propo sed to take advantage of the heat of 

 warm springs to hatch the eggs of hens and pigeons. This ingenious 

 idea has already been put in practice profitably at Vicky, in 1825, and 

 at Chaudes Aignes, in 1827. 



The "Maison Rustique" gives the following rules in regard to incu- 

 bation, and the management of the chickens : 



1. The apparatus designed for hatching should be in a still, retired 

 place, sheltered from the wind and from sudden changes of temperature, 

 and especially from noise and frequent jarrings, which are prejudicial to 

 the perfect development of the embryos. 



