AFP 



ch ngc takw place, this is exprefficd by '.he following dia. 

 giam, orfchcme. 



Muriat 



of 

 PoUlh 



"Muriatic Bcid 



water 60° 

 Potadu 



vSoda 



The fubftance to be dceompofoj is placed on tbc left 

 band, and is imincdiattly followed by a bracket whole point 

 is liimed towards tiie compound ; within the bracket are 

 the names of the two finiple fiibllanccs of which tjie com- 

 pound is formed, and parallel to one of them is the fub- 

 hance by whofc affinity a deconipofition was expefted : no 

 change however taking place, the fchenie is kit thus im- 

 perfiCt ; in the centre is the name of themenllruum and the 

 ttii'.peraturc in degrees of Falirinheit's iheimoraeter. 



Muriat of Potadi. 



-- . ^ f Mur. a. 

 I^^"™' J water lir 



Soda. b°^- 



l'oia(h 



This fchenie expalTes, that if to a boilinf; hot fohuion 

 of muriat of (oda in water, potadi be added, a decoinpoti- 

 tion takes place i muriat of potafh being formed, and the 

 Joda being fet at liljcrty : the llrait line under the ("oda, and 

 the pointlefs bracket under muriat of potafa, exprels that 

 both fubltances remain in folution. 



Sulphat of Strontian. 



Sulphat 



of 



Magnefia. 



Sulph. a. Strontian. 



water 60". 

 Magnefia 



Nitrat of Potafh. 



Carbonat f Potadi Nitric acid, 

 of -J water 60° 

 'otath. (.( 



Potath. / Carb. a. 



Sulphat of Soda. 



Sulphat f Sulph. a. Soda, 

 of i water 60"^ 

 Magnefia. ^ Magnefia. 

 < -, 



Muriat of Lime. 



Muriat 



of 

 Ammonia. 



1 



Mur. a. Lime. 



Fire. 

 Ammonia. 



Proof Spirit. 



Sulph; 



Solution r Water Alcohol, 

 of \ 



at. Soda. (.J 



_Sulphated Soda. 



A FF 



offinipk affinity: in the firft, we fee that rtrontlan added 

 to fulphated magnefia difTolved in water, at the ordinary 

 temperature, decompofes it, and produces fulphat of Jlron- 

 tian, and magnefia, both of which are precipitated. In the 

 fecoid, the addition of nitric acid, to a folution of carbo- 

 nated potadi, produces nitrat of potadi remaining in folu- 

 tion, while the carbonic acid h volatilized. In the third, 

 fulphated magnefia with foda, produces fulphat of loda re- 

 maining in fohition, and the m.ignefia is precipitated. lit 

 the fourth, dr>' muriat of ammonia and lime, heated together, 

 produce ammonia which is volatilized in the form of gas, 

 and muriat of lime remains behind. In the fifth, a folution 

 of fulphated foda being added to alcohol, the water and 

 alcohol unite together, while the fulphat of foda is precipi- 

 tated. 



It is impolTible to arrange the refults of experiments in 

 compound afiinity in a tabular fonn ; accordingly, fcliMnet 

 framed on the fame principles as thofe for fingle affinity, 

 have been adopted for the convenient regiftering of all the 

 known facts on this lubjeft. For example, the fatts tliat 

 fulphat of lime and muriat of putadi do not decompofe each 

 otlier ; and that muriat of llnmli.in, and fulphat of ammo- 

 nia do decompole each other, tugethir with the circum- 

 llanccs of fucli txperirnents are exprcfled in Uic nvg Wluw. 

 inir fchemcd. 



The above five fchemcs illuftratc all the remaining cafes 



Sulphat 



«f 



Lime. 



r Sulph. a. Potadi 1 

 4 water 60° |- 

 (_Lime Mur. a. j 



Muriat 



of 

 Potalh. 



Muriat of Ammonia. 



Ml 

 Strontian 



urlat rMur. a Ammonia. T Sulphat 



of i Water 60^ J- of 



antian. (^Strontian. Sulph. a. J , 



jlph. a. J Ajnmonia. 



Sulphat of Strontian. 



§ IV. Methods of ejlimat'tng numer'tcalh the force of eUdive ■ 

 Affinities. 

 Notwithftanding the vail importance of Geoffioy's tables, 

 and of all later ones conftruCled on the fame plan, it is ob- 

 vious that we can only learn from them the greater or lefs 

 degree of affinity which different fubftances have for the 

 fame body, according to the order in v.hich they are ar- 

 ranged ; and though this is fufficient for foretelling the re- 

 fult in cafes of fingle elective affinity, yet in more comph- 

 cated cafes, where the mutual attrafticns of four or more 

 fubftances are concerned, the want of a numerical exprcf- 

 fion for the force of affinity, in order to infer with any pro- 

 bability the refult of an untried experiment, niuft have for- 

 cibly impreffed the mind of every chemili. Thus, if the 

 refult of a mixture of nitrat of potafh with acetitc of lime 

 is required, all that can be learnt from the infpeftion of the 

 tables is, that the affinity of nitric acid for potadi is flrongcr 

 than for lime, and that the affinity of lime for acetic acid ia 

 weaker than that for potafh, or, to expicfs it in a tabu- 

 lar form. 



hence we have, 

 Quiefccnt affinities =/ + ■». 

 Divellent affinities =j + w. 



And 



