700 
Proceedings of the Pioijal Society 
universal Nature, let us say with the American Astronomers, that if 
this earth were touched by the Sun, and so sublimated by its terrific 
heat, that in a moment nothing of terrestrial substance would he 
left, except molecules and atoms vibrating in the intense light and 
temperature, — the H lines would be seen above, like a Solar red 
prominence, while the CO would be increasing its domain below. 
But would such a reproduction of Nebular haze bring hack the 
Chaos of the Greeks, or a reign of law and numerical order 1 
Let the last Plate of this paper (see Trans, vol. xxxii. part ii.), and 
its view of the beginning of the Green hand of CO now declare ; for 
Avhat was mere haze to smaller instruments is here proved by higher 
dispersion, conjoined with improved definition, to be a most curious 
and exact mathematical arrangement of lines, without one missing one. 
Op Elemental Gases. 
HYDROGEN. 
But if H, in CH, makes the carbon element behave so very 
differently to what it does when in the power of O, as CO, — how 
do H and 0 behave when single and separate'? Let us begin 
with H. 
Tubes of H vacuum are very bright to the naked eye, and to the 
spectroscope are multi-linear all the way along from Ultra Red to 
Violet. I have measured the places of 1625 of them. They form 
generally an open kind of groupings, occasionally exhibiting exqui- 
site specimens of close sharp doubles and trebles, but never enlisted 
into a rigid band system. It is rather a most free and aerial kind 
of atom dance from one end of the spectrum to the other in a pure 
H tube. 
OXYGEN, 
Oxygen, on the other hand, is a poor lighter up; and was declared 
by the British Association’s Committee’s Report in 1880 to have only 
4 lines in its spectrum, and those very faint. 
Those 4 so-called lines I have identified readily enough by place, 
and they are the brightest of the faint appearances in that spectrum, 
but there are many others to be noted. Three also of the first 4 
are triples of a very peculiar and uniform formation. They join 
too with three others which I have since discovered, in making a 
