so* 



*MEM0RIA TBCUNICA FOR ELECTIVE ATTRACTIONS. 



and sulphate 

 of barytes. 



Composition 

 according to 

 Klaprotli. 



benate of ammonia. The whole was evaporated to drvn 

 and then kept at a full red heat for a considerable time after 

 all visible fumes had ceased. The sulphate of barytes thus 

 produced weighed 110*75 grs. 



Then as 100 grs. of ignited muriate contain 73*14 ba- 

 rytesi ]00 parts of sulphate of barytes contain 



6(v04 barytes 

 33*9*5 sulphuric acid 



100. 

 The results of the above experiments nearly correspond 

 with those of Klaproth, according to whom 



Carbonate of barytes consists of j £* ">**?* *** 



J (78* 2 barytes. 



Sulphate of barytes 



C 33*55 sulphuric acid, 



GO' -55 barytes. 



and 100 parts of carbonated barytes yield l c 21'04 of cry- 

 stallized muriate. 



ARTHUR AIKIN. 



XIV. 



A Mefkoria Technica for double Elective Attractions. 

 Thomas Young, M.D. F.R.S. 



Tabic of dou- 

 ble elective at- 

 tractions. 



By 



SIR, 



To Mr. NICHOLSON. 



Have inserted, at the end of the Syllabus of my Lec- 

 tures on the Elements of the Medical Sciences, a short ta- 

 ble, containing the results of l c 260 eases of double elective 

 attractions. For the convenience of those who may wish to 

 retain these results in memory, I have since employed a few 

 leisure moments in expressing the table in the form of tech- 

 nical hexameters. I must beg leave to refer, for an expla- 

 nation of the principles on which the arrangement is 

 founded, as well as for a few particular doubts and excep- 

 tions, to a paper which will appear in the Philosophical 

 Transactions; and I shall at present only observe, that each 

 line expresses a column, of the table; and that when four 

 substances, which stand in any column, are mixed* they 



will 



