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Show COM.MUNICA TIONS BY 2. 52.-0CJwl' ./COMMUNICATIONS BY H. WEEKE~i: ESQ Rejer1·ed to at page 262 Dr.AR Sm-Since the d~tails of my first experiments on the prowction of acari in close atmospheres were given to the world, t~rough the medium of the "Proceedings of the London Electrical Socit>ty," sess;on of 18-l2, &c., and, about the same time, circulated among my scientific friends, in a reprint from the above-named work, as stated by you in a foot.note to page 187, first edition of the Vestiges, the subject has continued to occupy my attention, while the nature of my researches has been frequently modified by variations in regard to the form of the experiments, and their correl· ative arrangements. Incident to th~ period includ.od by the last three years, many expE-riments on the subject have been completed; others are even yet in prouress; and. however rigid were the cond' ions in any case adopted, thus much is certain. that the aca1'i ha1•e imm,··;abl-y appeared in the seveml sollllions under elect·rical influence, while thtir absence has been a im•a1'iably ,·emarkt•d, in spite of the nicest scrutiny, in all ne~ative tests provided to accompany the 1·especttve p1·imary upe1'iments. 'I' he following may he taken as an example of the stringent circum tances under which my latter experiments have been con· ducted; and although, in my own e~Umation, the evidence it yields is not one whit more conclusive than the results formerly made kno\vn, it i clearly free from certain objection w·~ed against the first experiment, a~d 1s sP.Jected under on impression that, if these conrlitioni fail to show that the electric current is the arrent by which the law of organization have been promoted. then we have -maugre the Baconian philo ophy-already tnt ted too much to exp •rim ntal fact . , with a view to the e tahli 'hmcnt of truth. Jt i& by no mean a. y, even if practicable, ind pendent ot 8ketches, to conv y a precise idea o( the appnratu mployed in th • cxp •rimcnt I am about to communicate. I will , ncv rlheless, att •mpt to de. rih • it with as much hr vity and plainne s as possibl . Tn the first pla , I must m •ntion that the arrangements w r originally of a thr •e-folcl har ct •r :- 1st. A lose vc sel containing a alin solution. and ahov it an artificial atmoRph re; 2<1. n open ' • . 1 containing the s ~tm« ! . olulion, both ~ctcd upon by th am curr •nt pa 1ng through them from a volt:uc .battery; 3d. Two gla jat tanding on th • . arne tahl , as negative te ts, and in vt"•ry v.:ay orr· ponding wilh the r •sp ctivc primary ves· s~ls, c. ·cf!pting that they had no wire app ndage , and were un· electrifi •ci. Th • clo o ,. sd con i t~ of a wide-mouthed glass jar, capable of containing n pint and. half of liquid, ancl is mnnufnctnrerl from th • pnr~~t and rno~t tran p:tr ·nt .mat ·r~al. . From the top, or shoul· dor of this jar n cend to th lw1ght ot an mch from the surround· lng aurfuc , n 'remarkably btout and strong neck, which present• W. H. WEEKES, E~Q. 2 |