On the general Nature of Light. l6t 



the water has thus been freed from all the phofphorifed hy- 

 drogen it had diflblved, it becomes pure water; which 

 proves that it was indebted for its new properties to the pre- 

 fence of this gas alone. 5th, In the lull place, that this 

 folution is capable of fpeedily reducing feveral metallic oxyds, 

 whether alone or diflblved by acids, and of forming with 

 them, by means of double electrive attraction, water and me- 

 'tallic phofphurets, combinations which hitherto have been 

 obtained only in the drv way ; that is to fay, by heating 

 metals with phofphorus, or by deeompofing phofphoric glafs 

 or metallic phofpliats by metals and charcoal. Such are 

 the properties which appear to me fufficiently interesting to 

 be worthv of being added to the ltill imperfect hiftory of 

 phofphorifed hydrogen gas. 



XI. On the general Nature of Light. By Mr. Robert 

 Heron. Cjmfiiumcated by the Author, 



X HE O UGH the medium of the Philosophical Maga- 

 zine I beg leave to lay before men of fcience the following 

 opinions, which have lately fuggefted themfelves to me as 

 neceflary and fait inductions from thofe facts that have come 

 to my knowledge refpecting light. 



1. Light pafl'es only through the vacuities in other bodies; 

 does not penetrate their folid fub fiance, fo as ever to coexift 

 with it in the fame place. 



2. It palTes through thofe vacuities in flraight perpendi- 

 cular lines, without any iofs of its qualities by attenuation 

 and fubdivifion of its particles : or, it is refracted from the 

 perpendicular with a fubdivifion of its particles, by which its 

 qualities are altered : or, its paflage is wholly interrupted, 

 and it is either reflected orablorbed. 



3. Since general attraction adts in bodies in the proportion 

 of their mafles and aggregation ; fince the more the affinity 

 of aggregation is in any bodies deflroyed, fo much the more 

 readily and powerfully do the chemical affinities of com- 

 position ait upon them; fince the extreme tenuity of light, 



Vol. VIII. Y the 



