COTTON. 



273 



Otton. 14th, full moon 21st, last quarter 29th. The chenille 

 on the 4th perceived partial on several spots of Success. 

 Towards the 10th, instead of suddenly disappearing, 

 and the pupae being exhibited in the manner I have de- 

 scribed, the larvae were universally seen languid and 

 motionless; and on the 15th they were every where 

 dead and putrid on the leaves. 



In the months of July, August, September, and Oc- 

 tober, we perceive the same causes giving life and ac- 

 tivity to the chenille; and until the 10th October we 

 also see that the ova were deposited and fecundated in- 

 to a fresh brood of the insect at the same periods of 

 each month. There are two circumstances particular- 

 ly remarkable in this period, which do not seem to have 

 existed in the preceding spring ; the first is the asto- 

 nishing quantity of thunder and lightning, and more 

 especially of that kind of corruscation, which, from the 

 time of the day in which it occurred, may be called 

 crepuscular lightning. This was more especially ob- 

 served on the 1 5th July, and on that day the chenille 

 was first perceived ; it is also singular that this did not 

 seem to be regulated by any change of the moon. 

 The same species of lightning also occurred in August, 

 and was nearly concomitant with the reappearance of 

 the chenille. The second circumstance is the extraor- 

 dinary fog in October, attended with an offensive sul- 

 phureous or hepatised smell. This had not been obser- 

 ved by me before ; but its effect on the chenille seems to 

 have been wonderfully great. The impregnation of 

 hydrogenous gas commenced on the 8th, and on that 

 very day the chenille began to languish, and by the 

 10th scarcely an insect remained alive, nor were there 

 the usual depositions of ova, nor apparently any pro- 

 vision made for a succession of the animal. This is 

 certainly a phenomenon of uncommon importance, be- 

 cause it points out, with tolerable certainty, the best 

 means of destroying the chenille ; and gives stability to 

 what has hitherto been little more than speculation, 

 viz. that the vapour of burning sulphur is the appro- 

 priate remedy for the evil. 



The consideration of the foregoing particulars seems 

 to lead to the following inferences : 1st, That lightning 

 and thunder dissipating obnoxious vapours, particularly 

 those of a hepatised and hydrogenous nature, and there- 

 by rendering the atmosphere more capable of aiding 

 the process of vegetation, favours the fecundation of the 

 ova, and the future progress of the insect to the perfect 

 moth state, by providing a fostering heat, and a larger 

 quantity of appropriate nourishment. 2d, That the ac- 

 cumulation of hepatised and hydrogenous gas in the at- 

 mosphere, by checking the process of vegetation, and 

 by having a direct morbid action on the organs of the 

 chenille, is inimical to their existence, and to their fu- 

 ture generation. 3d, That it is probably for this rea- 

 son that moderately dry weather, with north-east and 

 easterly and south-easterly winds, when the vegetation 

 of the cotton plant is most vigorous, favour the deve- 

 lopement of the insect, and that southerly and westerly 

 or land winds, tend towards then destruction ; the for- 

 mer being pure and uncontaminated by any noxious im- 

 pregnations, and seem rather, if different from pure at- 

 mospheric air, to be superoxygenated; the latter, on the 

 contrary, always more or less loaded with hydrogenous 

 or hydrocarbonic and hepatised gas, and being not only 

 destructive to the chenille, but in the highest degree 

 injurious to the human constitution. 



Although the planters anathematise this destructive 



VOL. VU, PART I. 



insect, with all the virulence of Ernulphus, it does not 

 appear that any thing effectual has been attempted to 

 prevent or destroy the evil. It is, however, of so serious 

 and important a nature, that something should be done. 

 Analogy points out the use of sulphureous vapours for 

 this purpose, and the direct effect of similar vapours 

 naturally applied to the chenille, confirms the proprie- 

 ty of the remedy. The Only objection to it of any 

 weight I have ever heard proposed, is founded on the 

 supposed expence in purchasing the apparatus, and on 

 the labour required for the effectual application of it to 

 the trees individually; for in no other way can it be 

 made effectual. But the judicious and truly economical 

 planter finds that the calculation of these gives a result 

 rendering them extremely trifling, when compared to the 

 prodigious loss sustained by permitting the evil to exist. 

 A small chaffing dish on which the sulphur is burnt, 

 and a painted canvass cone to be placed over the tree 

 for the purpose of concentrating the vapour, are all the 

 apparatus required; one person to hold the chaffing 

 dish under the tree, and another to place the cone over 

 it, are sufficient for each tree ; and ten minutes applica- 

 tion of the vapour, is all the labour. Now, if a gang 

 of 200 negroes, for all sexes and ages may be employ- 

 ed in this work, are put into a piece of chenilled cot- 

 ton, with 100 sets of the apparatus, they will destroy 

 the larvae and pupae spread over an acre in one hour, sup- 

 posing the acre to have 6'00 trees growing on it, which is 

 the usual calculation. — One acre of cotton trees in full 

 vigour, and uninjured by the evils to which the plant is 

 subject, will yield 400 lbs. of clean cotton, which at a 

 medium price will sell for s640 sterling. The apparatus 

 may be estimated at £60. — So that the expence be- 

 stowed on the destruction of the chenille of ten acres, 

 the probable amount of a day's labour of a gang of 200 

 negroes, will not exceed, including the first cost of ap- 

 paratus and the hire of the negroes, ^S0; while the 

 produce of the land gained by this expence will be 

 j£400, leaving a balance of £320; and the second ten 

 acres thus treated, as there will be no charge for ap- 

 paratus, will consequently give a clear gain of j£380. 

 But if we consider that if the remedy is not applied 

 there will be no produce, the magnitude of gain may 

 be estimated at a much higher rate. The adoption of 

 this remedy should therefore on no account be ne- 

 glected. 



A prudent economical planter will increase the brood 

 of every species of domestic poultry, particularly tur- 

 kies; for this has a tendency to diminish the brood of 

 chenille in a very great degree, while profit arises from 

 the augmentation of useful stock. Turkies are obser- 

 ved to have a remarkable appetite for the larvae of the 

 cotton moth, and devour prodigies quantities of them. 

 But the most usual natural enemy of the chenille is the 

 bird called in the colony Chenille bird, (the black 

 and yellow Manakyn of Edwards, or the Pipea aureola 

 of Linnaeus,) and the Certhia familiaris or house wren, 

 and the Par us Niger of Linnaeus, mentioned by Dr 

 Bancroft, (N. }lhi. of Guiana, p. 182.) The former 

 of these appears on the coast with the chenille, and 

 quits it at the same time it does, and the flocks are nu- 

 merous in proportion to the quantity of the insect. 



A remedy has been proposed and tried in England 

 for caterpillars, slugs, grubs, and other insects infesting 

 fruit trees and vegetable esculents, with considerable 

 success. I saw the experiment made by a gardener of 

 the name of Macpherson at Bath, and I had much rea- 

 2 M 



Cotton 



