59 [ 175 ] 



■quire several well-constructed thermometers. Those made with quick- 

 silver are always the most desirable, because the expansion and con- 

 densation of that metal arc more exact than those of spirits of wine. 

 The exterior sensations, and the disposition of the body, are often in 

 opposition to the evidence of the thermometer. These instruments 

 are therefore indispensable. The American cultivator of silkworms 

 must not be alarmed at being told, that a thermometer is an indispen- 

 sable instrument to his success: for ample experience has proved, 

 that it is impossible to ensure it without one; and no one should at- 

 tempt the business upon a large scale, and expect all the profit which 

 will result from liis labors and capital expended, unless the heat of 

 the rooms is thus regulated. We all know the extreme atmospheric 

 variations which often take place in the course of twenty-four hours, 

 and these are highly injurious to silkworms. The whole, or the 

 greater part, of a crop of worms, may be destroyed by a cold night; 

 or, if not destroyed, their growth will be checked, the spinning of 

 their cocoons be delayed, or rendered irregular and tedious; and they 

 will also be of a less size than when the heat of the room has been re- 

 igularly preserved. Thus, whether amusement or profit be the object, 

 a thermometer is essential. The instrument, as will be hereafter seen, 

 is also necessary to determine the proper degree of heat in the water 

 in which the cocoons are to be put to wind off their silk. 



It will be asked, do the people of Connecticut use thermometei^? If 

 not, do they not succeed without them.'* It is believed that they are 

 not employed:; and the consequences are, that millions of worms must 

 die from th-e causes mentioned; that the profit is thus greatly dimin- 

 ished; and that many worms which do survive, become debilitated, 

 spin small cocoons, and produce diminutive moths, and bad co-fs. 

 Hence the race is liable to degenerate. The peopleof Connecticut are 

 not aware of the importance of a thermometer, or they would not be 

 ■without one; and it only requires a single person among them to use 

 one, and thus to demonstrate his greater success, to induce the practice 

 to become general. The expense of a thermometer is trifling, and be- 

 sides its utility in the business of rearing silkworms, it will be found 

 a source of amusement to the owner and his family, throu^-hout the 

 year, b}^ enabling them to ascertain the precise temj)erature of the sea- 

 sons, and to judge of the comparative degrees of it in dillerent years. 



III. Of the hot-house, or room in which the silkworm should be 

 hatched. 



The first use of the thermometer should be in the liot-house, which 

 is destined for the hatchino; of the eo-o-s. 



As it may be more lavorabk; to our interests that the silkworm 

 should be developed whenever we find it convenient, and as this in- 

 sect must be reared in a season which, in our climates, has not the re- 

 quisite warmth, it is therefore indispensable to create an artificial tem- 

 perature suited to its progress. A small room or space should be pre- 

 ferred to a large one, as it is thus more easy to regulate the hent, and 

 as it also saves fuel. Silkworms have been Jiatched in a small a]);jrt- 



