2o3 Mr . Morgan’s Obfervations and Experiments on 
parts, and amongft thefe the particles of light in parti- 
cular ? 
III. Mu fl not this reparation of parts be great in proportion 
to the quantity of extraneous particles which are added to the 
bodjA ? Or (agreeable to the 4th obfervation) muff not the 
fpark be more fplendid and brilliant, the more the electrical 
fluid is concentered in any given fpace ? 
IV. In the diminution or alteration of that attractive force on 
which depends the conftitution of bodies, may there not be a 
gradation which, in the prefent cafe, as well as in that of 
burning bodies, will caufe the efcape of fome rays fooner than 
others 2 
Obfervations on phofphorlc light , 
It is obvious, from Mr. B. Wilson’s experiments, that 
there are many curious diverfities in the appearances of phof- 
phori. Some fhells, prepared agreeably to his directions, after 
expofure to the fun or to the flafh of a battery, emit a purple, 
others a green, and others a reddifh light. If with Mr. Wil- 
son we fuppofe, that thefe fhells are in a ftate of flow com- 
buftion, may we not conclude, that fome are juft beginning to 
burn, and therefore, agreeably to what I haveobferved on com- 
baftibte bodies, emitting the molt refrangible rays; whilft others 
are in a more advanced ftate of combuftion, and therefore 
emitting the leaft refranguble. If this conclufion be right, 
the fhells which are emitting the purple, or the green, muff 
flill retain the yellow, the orange, and the red, which will 
alfo make their appearance as foon as the combuftion is fuffi- 
ciently increafed. 
