132 
Proceedings of the Boyal Society 
Thickness 
of layer of 
liquid. 
Description of Spectrum. 
Arc 
measure- 
ments. 
Oscilla- 
tion fre- 
quencies. 
Wave- 
lengths. 
10 mm. 
Termination in the red, 
41°*4' 
1411 
7085 
Absorption band in the red 
overlying the Solar line C. 
Less refrangible edge, 
More refrangible edge, 
41°-20' 
41°-35' 
1490 
1560 
6711 
6410 
Visible spectrum ends at 
43 0, 48' 
2038 
4907 
A solution of chlorophyll, prepared from dried Anacharis by 
extraction with pure dried ether, was of a very bright green colour, 
when approximately of the same shade, and when seen in layers of 
10 mm. thickness, the spectrum measurements corresponding to the 
above were the following : — 
Thickness 
of layer of 
liquid. 
Description of Spectrum. 
Arc 
measure- 
ments. 
Oscilla- 
tion fre- 
quencies. 
Wave- 
lengths. 
10 mm. 
Termination in the red, 
41°-4' 
1411 
7085 
Absorption band. 
Less refrangible edge, . 
More refrangible edge, . 
41°T8' 
41°‘35' 
1480 
1560 
6754 
6410 
Visible spectrum ends at 
44° -14' 
2100 
4700 
In February 1884 I received from Mr John Murray a series of 
twelve bottles of spirit in which some of the “Challenger” dredgings 
had been preserved for periods of eight to ten years. They were 
labelled as follows : — 
1. St. 186, 8th Sept. 1874; Cape York; 8 fathoms. 
2. St. 151, 7th Feb. 1874; off Heard Isle; 75 fathoms. 
3. 7th March 1875; Admiralty Isle; 16-25 fathoms. 
4. 22d July 1874; Tongatabou ; 18 fathoms. 
5. St. 209, 22/1/75; Zebu; 95-100 fathoms. 
6. St. 157, 3d March 1874; 1950 fathoms. 
7. 23d Sept. 1874; off Arrou Isle ; 800 fathoms. 
8. 16th October 1874; 17 fathoms. 
