C O N T E N T S. 



M A K a. H' 1798. 



i. rthr'ervatior.t on Sirontian. Ry Citizen Pdleticr. Read to the National 

 ' Jnrtitutc", jo'li April 179') ^concluded from p. 522) — p. 529 



Caiimialcf of bmtcs and ftrootisn ttrnrcil with acids. The nitttitcj and tlitf mnriatf^ of ftrontian 

 aiid of lime aiioid a red fl.iire «:tiijilcoli'jl. — Stroiiiiin contains no lime — It is not precipitated by 

 nrunidtes, like ba;ytes— €• lukituent', ^larts .of tlic native carbonates. General concluliuns. Ad- 

 •<ftion«lct>B)l):>r«tire«Kferiiire«V«. ■ • l-.n . 



U. Abilrad of t-vo Meuicirs on 5 Method of obtaining Earytcs pv)rc, and on 

 the Properties cf tins Earth compared with thofc of Strontiaii. By Citizens 

 Fotircroy and Vaiqtielifi. Read to the National InUitute, 30th April and 

 21ft September i7^() _ '"' , , , ,^ • — — P' 53S 



Piopcttles of the pure ban tcs, oblaincd.by igqiting tbe nitrate. It is fufibic, crtlorcfccnt, folublc iu 

 water, ct7rtaHi»iMe, Ike. IVoperlies or ftrontian chiefly with rcfpeftto it« difJcicrice frbm barytes. 



III. Extract of a Letter from Count Muffin Pufchkin, Vice Prefident of the 

 Department of Mines at Pctetlburg. On the Salts, Precipitates and Amal- 

 gam of Platina ; on Cobah ; on Antimoaial Soap ; and on the Decompofition 

 of Soap by the acid ExtraAs of colouring Matters — — P- 537 



Brick-coloured precipitate by fal ammoniac is foluble in water. Otiicr precipitates. Amalgam. The 

 lingular properties. Cobalt. Antiinonial foap. Soap decompofed and charged with vegetable 

 colour. 



IV. Obfervations on the fundamental Property of the Lever. Widi a Proof of 

 the Principle afTumed by Archimedes in his Demonftration. By the Rev. 

 5. Vince, A.M. F.R.S. — — — — P- 54' 



Former demonftrations enumerated and examined. New demondration. 



V. Obfervations on the Acid of Tin, and tlie Analyfis of its Ores. Read at the 

 Sitting of the Clafs of Mathematical and Phiiolophical Sciences of the Na- 

 tional Inftitute of France, the nrft of MefTidor, in the Year 5. By Citizen 

 Guyton — — — — — p. 543 



Acidification of tin. State of this metal in certain ores. Analyfis and obfervations. 



VL On Fairy Rings — — — — p. 546 



Figure and caufe of fairy rings. Circles of burnt grafs produced by lightning. 



VII. Experimental Refcarches to afcertain the Nature of the Procefs by which 

 the Eye adapts iifelf to produce diftincfVifion — — P- 547 



Peculiarities of the eyes of fifhes. How the eye it adjuHed. Its difeafes. Indiftinftncfs. Double 

 vifion. Squinting. Difeafes of the cornea treated by Simulating applications. Cafe of Tubit in 

 the Apocrypha confirmed by modern praiftice, 



<; VIII. Ex- 



