ON THE ATOMIC GROUPING IN ORGANIC BODIES. 
897 
between the absorptions in the organic compounds and in the solar spectrum. Since 
the reading of the paper'"' we have further investigated these coincidences with greater 
prismatic dispersion and also with a diffraction grating of 17.260 lines to the inch. 
The indubitable result is that the broad line in the solar spectrum at X 866 is coin¬ 
cident with the radical line of benzine which in our scale is 856. Comparing the 
ethyl iodide group with the solar spectrum we find that the following bands are 
coincident with bands or lines in the solar spectrum: 880 to 888 with X 895 to X 903, 
888 to 892 with X 904 to 907, 898 to 902 with X 913 to 918, 902 to 912 with X 927 
to 930‘5, 912 to 920 with X 932 to 942. These bands are essentially the radical 
bands of the ethyl series. There are some more apparent solar coincidences in the 
spectra of water and chloroform. It is very remarkable that the line 856 in our 
scale should be the basic lines of the benzine series. When the thickness of benzine 
is gradually diminished this is the last line which disappears, but it remains of constant 
breadth to the end. Should it appear by subsequent investigations that the ethyl 
radical is really to be found in the solar spectrum it might be due to acetylene, from 
which immediately would follow the formation of benzine. 
Again, anyone who looks at a photograph of the solar A band and that of benzine, 
must be struck with the close structural likeness between the two ; it would not 
be at all surprising to find that X 760 was another nucleus for a hydrocarbon group. 
The X group of lines in the solar spectrum and that of the groups already mentioned 
appears to one of us to remain of constant intensity at any elevation of the sun or in 
any state of the intermediate atmosphere. It may therefore be necessary to refer them 
to some absorbing medium lying at the sun itself, or beyond the usually accepted 
limits of our atmosphere. Be it where it may, the fact remains that, in two instances 
at least, a study of the absorption spectra of organic bodies has to some extent thrown 
a glimmering of meaning on some of the absorption lines of the solar spectrum. 
The value of a study of the absorption spectra of liquids (not including in this term 
solids in solution) in order to gain an insight into their molecular constitution has 
been demonstrated by Professors Hartley and Huntingdon, and by their organized 
attack they have thrown much light on the subject; but we venture to think that 
the results we have obtained will prove that in these absorptions a still greater insight 
into the molecular constitutions of such bodies may be given. We may be too sanguine, 
but we believe not. It seems to us that the spectra leave as definite characters to 
read as are to be found in hieroglyphics, and we venture to think that we have given 
a clue to enable them to be deciphered. As to our theory that the foundation of all 
absorptions in these bodies is the hydrogen, we are content to leave it for discussion. 
If it should prove unreliable, the clue alone to the characters must be sought elsewhere: 
the story is still to be read by any one who may find a better one and a truer. Fully 
conscious of this, we would invite an exhaustive discussion, deeming that the results 
alone, which are indisputable, will give a ready basis for it. 
MDCCCLXXXT. 
* March, 1881. 
5 z 
