X CONTENTS. 



OCTOBER 1800. 



Engravings of the following Objefts : 1. Mr. Clofe's new Engine for raifing 

 Water by the lateral Communication of Motion. 2. Dr. Wollafton's Figures 

 to illuftrate the Appearance of double Images produced by Atmofpherical 

 Refra£tion. And, 3. Dr. Herfchel's Apparatus for afcertaining the EfFefts 

 of the invilible Rays of the Sun 



I. A Projeft for extending the Breed of fine-wooled Spanifh Sheep, now in the 

 , PofTeffion of his Majefty, into all Parts of Great Britain, where the Growth of 



fine clothing Wool is found to be profitable - - p. 289 



The King having procured fdme Merino iheep of the firft charafler for the finenefs of their wool, 

 and having caided a number of judicious trials to be made, by vviiich it is afcertained, during 

 the courfe of above feven years, that the quality does not degenerate, but maintains all its ori- 

 ginal finenefs in this country ; and the value of the wool being now known to our manufafturers. 

 His Majedy has been pleafed to give away to different perfons, for experiments, more than one 

 hundred rams and fome ewes : and flill t'urther to extend this valuable improvement in our flaple 

 commodity, he is now pleafed to permit fome ewes and rams to be fold at moderate prices. 

 The management of this bufinefs js committed to the Right Honourable Sir Jofeph Banks, to 

 whom letters may be addreffed. 



II. Defcription of an Engine for raifing Water by the lateral Motion of a Stream 

 of Water through a conical Tube. In two Letters from Mr. William Clofc 



p. 295 



Water flows out of a ciftern through the conical pipe of Venluri. Into the throat, or fmalleft part 

 of this pipe, is infertedan air tube, proceeding from a veffel in a more elevated fituation. The 

 coniequence of this arrangement is that the air in the upper veffel is rarefied, and water rifes into 

 that veilel through a vertical pipe. As foon as the velTel is nearly filled, its contents are deli- 

 vered by an apparatus, wliich is contrived to perform the requifite alternations without 

 attendance. 



III. On double Images caufed by Atmofpherical Rcfraftion. By William 

 Hyde W^ollafton, M. D. F. R. S. - - p. 298 



Short enumeration of the fa6ts. General laws of the theory of Refradions, near the place ofcon- 

 taft and admixture of fluids differing in dcnfily. Experiments to confirm the theory, by includ- 

 ing {yrup and water and alcohol in the fame veffel ; by means of which double images and inver- 

 lion ofobjedls are produced. Otlier fluids. Hot water carefully placed upon cold. Heated 

 air in the vicinity of red hot iron. Obfervations on the ordinary effects of folar heat. Experi- 

 ments and obfervations with ether, alcohol, and water, to fliew how far evaporation is concerned 

 in thefe effects. 



IV. A Memoir on the Nature of the colouring Principle of the Lapis-lazuli. 

 By Citizen Guyton - - - - p. 308 



The fulphate of lime of Montolier is coloured by a red oxide of iron, which, by treatment with 

 charcoal, affords a fulphuret of iron, in which the metal is lefs oxided, and which, byfolution 

 in acids, aiid precipitation by a prufliate, affords not Pruflian blue, but agreendepofit of a dif. 

 fcrent nature ; which fulphujet preferves its blue colour in pot-alh even at the beat of fufion, A 



fimilar 



