624 



FARMERS' REGISTER 



lieve to be still more polent, namely, the very 

 inefficient manner in wiiich ihe eg^s of the silk- 

 worm were preserved and retarded lor late rear- 

 ing?, thereby rendering worthless a stock origi- 

 nally good. Ii is obvious that the process of re- 

 tarding should be commenced early in the winter, 

 before the accession of warm or moderate weather 

 has had any influence on tlie condition of the em- 

 bryo. The object is to prolong the winter through 

 which the eggs have to pass previous to hatching ; 

 in other words, to continue them in precisely the 

 same state in which they exist at the beginning of 

 cold weather. If they are sufiered to be exposed 

 for a few weeks, or even a few days, to mild wea- 

 ther, such as almost uniformly occurs in February, 

 some degree of change must necessarily take place 

 in the condition of the eggs ; and if their progress 

 towards the hatching stale be suddenly arrested, 

 the effect must inevitably be injurious. They 

 should also be preserved in an equable tempera- 

 ture, as nearly at 40 degrees as possible. The 

 fluctuations of temperature are greater even in an 

 ice-house, at the surface of the ice, than one 

 might suppose without having verified it by an in- 

 strument. The atmosphere of a box, resiing im- 

 mediately on the ice, will vary according to the 

 state of the weather from 45 to 55 degrees. Im- 

 bedded in the ice, it will range from 37 to 45 de- 

 grees. But it is not alone by subjecting silk- 

 worms' eggs to a low temperature, that iliey will 

 be preserved uncorrupled. If the air be foul, ei- 

 ther from decaying wood or other vegetable mat- 

 ter, or from a want of circulation, the good qua- 

 lity of '.he eggs will suffer deterioration. It is 

 therefore necessary that some substance be used 

 to correct the gaseous impurities that may be ge- 

 nerated ; and the simplest and most efficacious 

 agent for this purpose is charcoal. A quantity of 

 it well pulverized, should he placed in the boxes 

 or vessels containing the eggs. In addition to all 

 this, the eggs must be kept dry. When taken 

 out for hatching, tliey should be gradually ex- 

 posed to the external air ; and the contents of the 

 box should seldom or never be subjected to the in- 

 fluence of the warm air, even fnr a moment, until 

 they are taken out to be hatched. 



I respectfully submit whether these con-ditions 

 for preserving and protracting the hatching of 

 eggs are not rational? And if they are, what a 

 fruitful source of disease and disaster has arisen 

 from disregarding them. They have probably 

 not been complied with in one case out of ten. I 

 feel warranted therefore in repeating that the ne- 

 glect or omission to take proper care of the eggs, 

 is perhaps one of the most potent causes of the 

 evils to which the silk culturist has been subjected. 



But notwithstanding every precaution in pre- 

 serving the eggs, it is still very possible, not to say 

 probable, that the hatching may be protracted so 

 far beyond the natural lime as to render them un- 

 fit for the production of a healthy progeny. No 

 process of retarding has been devised by which 

 the tendency to hatch has been entirely arrested 

 or suspended. Some advancement towards the 

 hatching condition, however gradual, will be made 

 even at the lowest temperature to which eggs can 

 be conveniently subjected, when ihey are kept 

 much beyond the natural period for them to hatch. 

 There is great reason to believe that a want of due 

 attention lo this Itict may be added to the other 

 cayses of failure ; and that before p en'ccl success 



n the rearing of successive crops can be attained 

 — if attainable at all — the cultivators of the silk- 

 worm must provide themselves with a slock of 

 eggs saved at successive periods during the sea- 

 son. This view of the subject has been strongly 

 presenied by Gideon B. Smith, who has founded 

 upon it what may be termed a new theory, which 

 he has recently promulgated and endeavored to 

 establish. The basis of his theory is the fact that 

 the eggs of the silk-worm naturally hatch at the 

 expiration of one year from the hatching of the 

 preceding generation ; and the deduction is that 

 ihe farther the hatching is removed by artificial 

 means beyond the natural time, the more liable is 

 the progeny to degeneracy and disease. To what 

 extent the hatching may be safely postponed, can- 

 not at present be determined with precision. Mr. 

 Smith adduces ficls to show ihat it may be ex- 

 tended one month beyond the natural lime, with- 

 out impairing ihe good quality of the eggs ; and 

 by exercising judicious care in the preservation of 

 the eggs, the period may be still further postponed. 



Since the publication of this theory, I have en- 

 deavored to test its claims lo acceptance by re- 

 viewing the facts which have come under my ob- 

 servation during (he two past seasons ; and I feel 

 bound to state that it offers a solution for many 

 difficulties which were before inexplicable to my 

 apprehension. It is, moreover, a rational theory, 

 and in harmony with Ihe laws of nature. It com- 

 mends itself therefore to the serious attention of 

 those who intend lo persevere in silk culture in 

 spite of the disasters of the present year — disas- 

 ters which it may be reasonably hoped are only 

 temporary, and capable of being obviated by the 

 use of such precautions as the subject merits and 

 requires. Further experience may lead to some 

 modification of the details without invalidating the 

 principle. 



You have contrasted the resulls of the past and 

 present years in rearing silk-worms, but have not 

 attempted to account for the difference. May not 

 Mr. Smith's theory explain the mystery most sa- 

 tisfactorily? In the year 1839 all our late rearings 

 were from northern eggs. The season was not 

 less wet and unfavorable in every respect than 

 that of 1840. Now it is well known that during 

 the continuance of the mullicaulis mania, the ex- 

 perimenters with silk-worms could not obtain fo- 

 liage earlier than June or July. The sole reliance 

 was on the leaves of young trees raised from buds 

 planted the preceding spring, and from roots trans- 

 planted. All the eggs therefore which were re- 

 ceived from the north must have been derived 

 from worms hatched not earlier than the fore part 

 of June — in many cases from even later broods. 

 Such eggs, if of good quality, should, according 

 to Mr. Smith's system, have produced healthy 

 worms if hatched within thirteen months from 

 the hatching of the parent generation. The late 

 rearings in Virginia last year were attended with 

 resulls which gave general satisfaction and en- 

 couragement. It is but fair therefore to presume 

 that those results were modified by the principle 

 on which Mr. Smith's theory is founded. And in 

 all instances where I have been able to learn the 

 facts and dates, the late rearings of this year, de- 

 rived from the late rearings of last year, have been 

 attended with much better success than those de- 

 rived from spring-laid eggs, long retarded. But 

 in the general ignorance of the principle adverted 



