124 Harttey—An Investigation of the Connexion between 
differs in its constitution from the bands described below, in the more refrangible 
rays, as these are all degraded towards the red. 
(2) A diffuse composite band lies between dX 5100 and 4700 less strong than 
the band (1), but composed of anumber of fine narrow bands. ‘These constituent 
bands are likewise diffuse, but are better defined than those in (1). 
(3) A diffuse composite band lies between A 4650 and 4279. ‘This is a very 
strong band, composed of a great number of very fine lines, all of which are very 
sharp. 
(4) Between \ 4279 and 4000 is a strong band, composed of a series of fine 
sharp lines degraded towards the red, and of diminished intensity as compared 
with (3). A sharp composite band. 
(5) Between d 4000 and 8800 is a similar band of fine lines, much fainter 
than (4). A sharp, composite band. 
In addition to the bands the line \ 3274 also appears strong. The similar 
line belonging to this spectrum at 3248 falls just beyond the edge of the 
photographic plate, when the instrument, as in this case, is adjusted for 
photographing the extreme red rays. 
Quantity of 
0-1 gr. The intensity of the whole spectrum is much reduced. 
Bands. 
(1) A diffuse composite band, fairly strong, between A 5800 
and 5100. 
(2) A diffuse composite band between \ 5100 and 4700, feeble. 
(3) A sharp composite band between \ 4650 and 4279, rather 
strong. 
(4) A sharp composite band between \ 4279 and 4000, very 
feeble. 
(5) The band between d 4000 and 3800 is quite extinct. 
Lines \ 3274 rather strong. 
0-01 gr. A very feeble spectrum throughout. 
Bands. 
Between d 5800 and 5100, a feeble diffuse composite band. 
Between \ 5100 and 4700, band extinct. 
Between \ 4600 and 4279, a feeble sharp composite band. 
Between \ 4279 and 4000 the band is extinct. 
Line \ 8274 is feeble. 
0-001 gr. No bands. The line \ 3274 is just visible. 
0-0001 gr. Nothing visible. 
Norn. -— A close connexion between the diffuse and sharp bands is an 
important feature of the copper spectrum. ‘Thus, the diffuse composite band 
