98 PARTICLES OF LIGHT IDENTICAL 



In accordance with the hypothesis advanced 

 by Newton in one of his Optical Queries, that 

 light and common matter are mutually convertible 

 into each other, it has been recently maintained 



convertible into light, and that light is decomposable into seven 

 primitive rays by prismatic refraction, as maintained by Newton, 

 or into only three fundamental colours, when analyzed by ab- 

 sorbent transparent media, as maintained by Brewster, it will 

 follow that what we call simple bodies are composed of one, two, 

 three, or more of the primitive elements which constitute white 

 light. Now it is worthy of remark, that hydrogen is the most 

 elastic of all gaseous bodies, and affords during combustion an 

 almost perfectly blue light; while according to the experiments 

 of Newton, the blue rays are more refrangible than any others 

 except the violet, which is not a simple colour according to 

 Brewster, but composed chiefly of blue, with small proportions of 

 yellow and red; which he regards as the three primitive rays, and 

 the elements of all compound colours. It is therefore probable 

 that the blue and violet rays are more refrangible than the others, 

 for the same reason that hydrogen, of which they are formed, is 

 the most elastic of all known bodies; viz. because it contains 

 more caloric around its particles in proportion to their size. And 

 it was supposed by Newton that the atoms of light diminish in 

 size from the red to the violet extremity of the spectrum. Again, 

 as sulphur burns with a blue, and iodine with a violet light, 

 (which contains small proportions of the other rays,) they may 

 be composed chiefly of hydrogen, with some other base or bases ; 

 and cannot be otherwise decomposed than by expanding them 

 into the subtile form of light. On the other hand, during the 

 combustion and ignition of potassium, strontium, barium, lithium, 

 sodium, and magnesium, they afford chiefly red light, with small 

 proportions of the other coloured rays; therefore must all be 

 composed principally of one element, the primitive atoms of which 

 are red, while those of hydrogen (which is the basis of sulphur, 

 iodine, and perhaps some other bodies) are blue. Hydrochlorate 

 of calcined soda also affords an orange coloured light ; while in 

 that of chlorine, silver, copper, and some other bodies, there 

 is a predominance of greenish rays; so that if green light be 

 composed chiefly of yellow and blue, as maintained by Brewster, 



