170 REPORT—1868. 
ference for Sirius. As his experience in making such comparisons is greater 
than mine, I leave to him the solution of this question, satisfied that the first 
proposal of this method for determining the proper motion of the stars, which 
I made in 1863, has been well received by such a competent judge. 
T will conclude with a few words on the nebulz, and especially on that of 
Orion. I have the honour to exhibit a drawing of it, made with every care ; 
it is intended to show how far we may see with a single 94-inch object-glass, 
leaving to your gigantic instruments to penetrate more deeply into these 
wonderful objects. I shall only say that on the other side of the galaxy I 
haye examined several nebule, and found them to haye the same spectrum 
as @Orionis, A difficulty, however, arose in my mind about this subject, which 
is as follows:—How can it be that while hydrogen gas has so fine and rich 
a spectrum, we do not see in the nebule anything except the simple line F? 
I undertook, therefore, a kind of photometrical discussion of the intensity of 
luminosity of the different lines which constitute the spectrum of this sub- 
stance ; and the result is that, in diminishing the light by an absorbing screen 
and simple reflections, we could reduce the spectrum to a single line F, as we 
see it in the nebule. Even hydrogen burning at the ordinary temperature 
has not given any line besides this after reflection, The difficulty is there- 
fore completely removed, being only a question of intensity of light. 
Here you see that the matter is not exhausted. We want yet to make a 
more thorough review of our discoveries to settle many doubtful points. It is 
for the chemical philosopher to resolve some of these difficulties, the astrono- 
mer can walk here only with the lamp of chemistry. We haye already had 
great satisfaction in seeing quite lately that the brilliancy of a comet was due 
to the rays of carbon*, Ere long we shall more accurately know what main- 
tains light and heat in so many bodies which are scattered in the profundity 
of space, 
Report on the Physiological Action of the Methyl and allied Compounds. 
By Bensamin W. Ricwarpson, M.A., M_D., FR.S. 
Durine the past twelve months, in accordance with the request of the Asso- 
ciation, I have continued my researches on the physiological: action of the 
methyl compounds and their allies. JI have had in this research four 
objects in view :— 
1, To bring into actual practice as remedies some of the substances the 
physiological action of which I had already ascertained, and on which 
I had previously reported. 
2, To examine further the special mode of action of those bodies of the 
series which will produce sleep and insensibility to pain—the ane- 
sthetics of the series. 
3. To inyestigate the action of some other bodies of the series, which 
have not as yet been studied by the physiologist, in relation to 
anesthesia. 
4, To test the antidotal influence of some of the compounds against the 
action of certain active alkaloidal poisons. 
To render the Report systematic, I shall place the subject-matter under 
the heads above named, 
* The discovery of the lines of carbon was made by the author and communicated to 
the French Academy while Mr. Huggins was independently discoyering the same thing. 
