210 CLASS AVES. 



ployed, such as those of bakers, confectioners, &c., or pre- 

 paring chambers, which he heated by a stove, observing in the 

 first case to modify the heat, and in the second to regulate the' 

 fire, by the assistance of his thermometers, so that during the 

 twenty-one days necessary for the incubation of the eggs, the 

 temperature should not be below twenty-eight degrees, or 

 above thirty-four. 



By dint of perseverance, address, and care, Reaumur suc- 

 ceeded in managing these operations very well. But they 

 involve so much trouble and difficulty to the persons to whom 

 their execution must of necessity be confided, that, since his 

 death, nobody has thought proper to adopt them. They pro- 

 duced the effect, however, of inducing other natural philo- 

 sophers to search for methods less defective, and more cleanly, 

 with a view to an establishment of this kind on an extensive 

 scale. M. Chapineau, author of a book called " Homme rival 

 de la Nature,'''' has in particular shewn a vast deal of intelli- 

 gence and ingenuity in his attempts in this way. 



His hatching-room or house, is a round building, the top 

 of which is a vault, with four triangular windows, each open- 

 ing at pleasure by means of a cord passed into a pulley. The 

 entrance of this room is by two glass doors, one internal, the 

 other external. Both these, as well as the windows, are pro- 

 vided with bands of lambskin, and to the last door is a cur- 

 tain of thick woollen stuff". The exterior of this little build- 

 ing, to three-fourths of its height, is also covered with pieces 

 of cloth. In the interior, circular tablets are arranged, on 

 which the eggs are disposed, and which may contain about 

 eight thousand. Between each tablet are four pipes, opposite 

 to each other, for the purpose of distributing air ; and 

 which open and shut externally. In a chamber below this 

 hatching-room, a stove or furnace is constructed, into which 

 is dipped, about two feet deep, the base of a copper column, 

 filled with water, heated to a suitable degree by the fire of 



