74 Obfcrvatlons on Spiders, 



of wool and greafe, held down by a plate of metal faftened 

 by Icrews. i is a plate of copper, concave, or rather conical 

 below, ftretching almoft to the fide of the ftill ; m a large 

 hole in the centre of this plate, through which the fteam 

 generated at the bottom of the ftill efcapes into the head. 

 This plate, being made of quick afcent, facilitates the cfcape 

 of the fteam, which might otherwife be partially accumu- 

 lated under the lliouldcr of the ftill, and, by its re-a£lion on 

 the fubcumbent liquor, caufe the ftill to run foul, or boil 

 over. /J /^ the head of the ftill. To the fcraping-machine _/ 

 are attached chains, which, by the rotary motion of the 

 fcraper, are drago;cd with rapidity over the whole of the bot- 

 tom, by which means the wafti is prevented from burning 

 to the bottom, and thereby generating any new compound 

 injurious to the flavour or quality of the fpirit. Thefe ftills 

 are ufually of from 40 to 50 gallons contents. 



The principle of the improvement feems to centre in this 

 fimple point — The greater the quantity of heat that can be 

 made to pafs through the body of the ftill in a given time, 

 the greater will be the quantity of vapour, and confequently 

 of fpirits, produced in that time : and certainly it is not eafy 

 to conceive iiow this can be attained in anyway fo efl'eftually 

 as by making the ftill all bottom, as It were, and applying the 

 heat to every part of that bottom. 



X\'. Ohfervatloiis on Spiders, and their fuppofed Po'ifon. 

 Bj M. A-M OREV X jun. iV. jD.* 



T: 



HIS genus of infefts is as numerous in fpecies as the 

 latter are varied. France contains almoft the half of the fpe- 

 cies known. M. Geoffrey has mentioned only fi^^teen ; but 

 Dr. Lifter, who made obfcrvations of^the fame kind in Eng- 

 land, and M. Clerk, who carried them as far as any one in 

 Sweden, have given a more complete hiftory of them. Sco- 

 poliy locomn.endable in other refpefts for his ufeful labours, 

 does not appear to have done right in changing entirely the 

 denomination of forty-four fpecies of fpidcrs, which he faw 



• From Notice des Infixes de la France re^tuU venimeux. 



