Mallcalle Platina. — Lectures. SS? 



frequently placed a spider on a small upright stick, whose 

 base was surrounded by water, to observe its most sinoular 

 mode of escape. After having discovered tliat the ordinary 

 means of retreat arc cut off, it ascends the point of the 

 stick, and, standing nearly on its head, ejects its web, which 

 the wind readily carries lo some contiguous object. Along; 

 this the sagacious insect effects his escape, not, however, 

 till it has previously ascertained, by several exertions of its 

 whole strength, that its web is properly attached at the 

 opposite end. I do not know that this instance of the 

 sagacity of the spider has been noticed by any entomolotncal 

 writer ; and I insert it here, in consequence of having seen 

 in some periodical publication, a very erroneous account of 

 the origin of the spider's threads which are observed to pass 

 from one tree or bush to another in dewy mornino-.s." 



MALLEABLK PLATINA. 



Our chemical readers will be gratified to be informed that 

 this valuable and useful article can now be procured at a 

 price that will put it in their power to employ it in utensils 

 for various delicate purposes. The following articles, made 

 of pure platina, may be had of Mr. Carey, mathematical 

 instrument maker. No. 182, in the Straud. 



Crucibles of various sizes, with or without covers, at 

 17s. fid. per ounce, with a small addition for workuiau- 

 ship. — Evaporators, about 5 inches diameter, weighiniT be- 

 tween 3 and 4 ounces, at the same price. — Wire of various 

 siz-es, and laminated platina, at iGs. — Bars of malleable 

 platina unmaiuifactured at 13s. per ounce. Other articles 

 may be made in a sliort time, according to order, by fur- 

 nisliiiig Mr. Carey with a drawing or correct description. 



LECTURES ON PHYSIC AND CDKMLSTRY. 



On Monday, .June 3d, a Course of Lectures on Physic 

 and Chemistry will rcconnnence at the Laboratory in Wiut- 

 comb-street, Leicester-square, at the usual morning hours, 

 viz. the Materia Mcdica and Therapeuticks, at a quarter 

 before eight ; the Practice of Physic, at half after eight; 

 and the Chem.istry, at a quarter after nine; by George 

 Pearson, M.i). F.R.S. Senior Physician to St.' George's 

 Hospital, of the College of Physicians, &c. Sec. 



Note. — The Practice of Vaccmation will be taught at the 

 Institution in Broad-street, Golden-square, and an ac- 

 count will be given of the practice on the patients in St. 

 George's Hospital, as usual, every Saturday morning, at 

 nine o'clock. 



Proposals may be had at St. George's Hospital, and at 

 52, Leicester-square. 



