56 REPORT—1849, 
we have a regularity of arrangement equally accordant with our preconceived 
notions of the order which should subsist in a regular independent system. 
The very elongated elliptic annular nebulz, where the minor axis is some- 
times almost evanescent, show us pretty clearly the nature of the slight, long, 
dark and nearly straight streak in some cases found parallel to the axis of a 
long ray. A little consideration of the appearances which annular and spiral 
systems must present when viewed in different positions, in some instances 
affords a pretty satisfactory explanation of the confused streakiness we have 
observed in several of the nebule. 
This, however unsatisfactory it may appear, is the best explanation our 
working journal-books at present afford of the streaks observed by Mr. Bond 
in the nebula of Andromeda. 
Mr. Bond’s paper has excited so much interest, and I have been so often 
questioned relative to it, that I have prematurely, in anticipation of more nu- 
merous sketches and measurements, which will probably throw additional 
light on the subject, ventured to lay before the Association the very little, 
which is at present known to us. 
It was in the spring of 1846 that we first perceived the brighter portions 
of the nebula of Orion in the neighbourhood of the trapezium breaking up 
into minute stars. Whenever the sixth star was nicely separated, this appear- 
ance was clearly perceptible. We had repeatedly examined Orion with the 
telescope of three-feet aperture, without a suspicion of its being resolvable ; 
however, its resolvable character once known, we were enabled with it on very 
fine nights to see some of the stars. With the six-feet telescope, the space 
within the trapezium is still dark, just as Herschel describes it, and I feel con- 
vinced there is no optical illusion. 
Last season my attention was directed by Mr. Stoney to « Orionis, which is 
on the edge of a dark spot; the dark spot includes the nearer companion, 
and is about 12” diameter; we have not yet had an opportunity of examining 
it with the great instrument. 
A few copies from our collection of sketches accompany this notice: they 
have been made within the last day or two by a drawing-master in the neigh- 
bourhood. He has transposed white for black, and enlarged the scale to 
make them more suitable for exhibition in the Section. 
In sketching, we employ solely the black-lead pencil, black representing 
light, and the eye by habit makes the transposition without effort. 
The copies are not quite accurate, but they are sufficiently exact for the 
purpose. 
On the Influence of Carbonic Acid Gas on the health of Plants, espe- 
cially of those allied to the Fossil Remains found in the Coal For- 
mation. By Professor CHaxues G. B. Dauseny, M.D., F.R.S. &. 
« Ar the Meeting of the British Association for the Advancement of Science 
held at Oxford in 1847, it was resolved, that a Committee, consisting of Sir — 
H. T. De la Beche, Sir W. J. Hooker, Dr. Daubeny, Dr. J. D. Hooker, 
Mr. A. Henfrey, and Mr. R. Hunt, be requested to investigate the influence 
of carbonic acid on the growth of plants allied to those found in the coal 
formation.” 
This investigation was accordingly entered upon by myself in the spring 
of 1848, by means of an apparatus consisting of two jars of corresponding 
size, each containing about 2800 cubic inches of air, the edges of which _ 

