46 Richard Adie, Esq., on the Connection between the 



themselves, but magnetic in many of their compounds; and the third, 

 diamagneLic metals. In reading over the descriptions of nearly 1500 

 combinations for this purpose, some, the majority of which are pro- 

 bably colourless, had to be omitted for the want of an explicit state- 

 ment about colour; but by pursuing a uniform principle in the classi- 

 fication of all, the results, it is hoped, are nearly the same as would 

 be obtained by the more rigorous method of examining in the hand 

 each substance before classifying it. 



To compare these numbers together in order to shew the relative 

 proportion the transparent or white bodies bear to the coloured in 

 each class, a common integer is found to convert the former into 100, 

 thus — for every 



100 White Oxides of Magnetic Bodies, there are 336 Coloured. 



,, „ Diamagnetic, „ 47 



„ Compounds of the 3 Magnetic Metals, 400 



3 Feebly, „ 259 



,, » jj 5 Diamagnetic, 63 



Giving proportions which do not materially differ from those I had 

 previously derived from the tables of the colours of the precipitates 

 by the re-agents used in testing, but being founded on the descriptions 

 of a much larger number of combinations, are more satisfactory as 

 evidence of the general tendency of magnetic bodies to form coloured 

 combinations; the difference between these and the diamagnetic, as 

 derived from Gmelin, being as 400 to 63. 



Carbon^ Nitrogen, and Hydrogen. — These elementary bodies in 

 their combinations with one another, give compounds which, on the 

 torsion balance, shew very clearly the influence of colour on magnetic 

 properties. Carbon and hydrogen form turpentine and naphtha, 

 colourless diamagnetic fluids. Carbon and nitrogen form cyanogen, 

 a colourless gas, strongly diamagnetic, according to Faraday; they 



