166 
To the Editor of the Monthly Magazine. 
SIR, 
HE lucid appearance of the sea, 
appears to arise from two causes. 
1. Phosphorescent living animals. 2. Ani- 
mal matter, phosphorescent after death. 
1. Phosphorescent living animals have 
been proved, by the most undoubted 
authority, to cause, in some cases, the 
luminous appearance of the sea. Prof. 
Mitchill,* gives us an account of an ap- 
pearance of this sort, to which he was 
witness, and which was caused by ani- 
maicula (clnefly mollusca animals), some 
of which, (he presomed the nereis noc- 
tiluca,) were so small and pellucit, as, 
with the naked eye alone, not to be dis- 
tinguished by day-light, in a glass of 
water. But on agitating the water in the 
dark, beautiful emissions of light were 
observed, 
that a long continuance of light cannot 
be emitted by the same animal. “ There- 
fore the light emitted by the motion of 
the waves, is caused by a succession of 
animals, each of which, on being stimu- 
Jated, evolves in its turn a certain pro- 
portion and duration of light.” 
We are also informed by M. Peron,+ 
of a luminous appearance of the sea, like 
a vast sheet of phosphorus floating on 
the waves; but which proved, on a 
nearer approach, to be an immense num- 
ber of zoophites, borne by the water at 
different depths. Those which were on 
the surface, resembled great cylinders of 
iron; whilst those which were deepest, 
appeared like red-hot eannun-balls. 
2. Animal matter, phophorescent after 
death. This phosphorescence commences 
at a certain time after death, but before 
putrefaction commences. Cantont. ob- 
served, that sea-water became luminous 
after remaining some time over the sub- 
stance of a fresh herring. Dr. Hulme§ 
discovered, that saline solutions, such as 
sulphate of soda, muriate ef soda, and 
sylphate of magnesia, were possessed of 
the same property. About four drams 
of the substance of a fresh herring, being 
allowed to remain for two days in a 
solution of two drams of sulphate of mag- 
nesia, in two ounces of cold water; on 
* Phil, Mag. vol. x. p. 20. 
Professor Mitchill. 
t+ Journ. de Phys. and Retrospect of Phi- 
Jusophical, Chemical, and Agricultural Dis- 
€overics, vol.i. p. 36. 
}~ Marray’s System of Chemistry, vol. i. 
p- 510. ‘ 
§ Philosophical Transactions for 1800. 
A letter by 
Causes of the lucid Appearance of the Sea. 
The same letter informs us, ° 
[Sept. ly 
examining the liquor, a lucid ring was’ 
observed on the surface, and on agita- 
tion, the whole became beautifully lumi- 
nous. In a little time, the- luminous 
mattersubsided ; but by agitation, it again. 
became luminous. 
exposed to the air were luminous ; while 
the parts not so exposed, remained dark. - 
The luminous appearance was impaired 
by cold, and made more’splendid by a 
moderate heat; but. destroyed by the. 
heat of boiling water. 
Hence the luminous matter may, dur. 
ing the heat of summer, by the dashing - 
of the waves, be brought to the surface 
exposed’ to the atmosphere, and made 
beautifully, but transiently, phosphores- 
cent. | 
Your's, &e.” 
October 12, 1808. T. Brewerrton. 
, ——a 
To the Editor of the Monthly Magazine. 
STR, ) 
Hew been some time ago en- 
gaged, pretty extensively, in the 
refining of sperma ceti, and never having 
seen an account of the mode of refining 
it in any way satisfactory, Iam induced 
to send this for insertion in your Maga- 
zine, It istrue, had I any connections 
with those gentlemen who have the 
honour of affixing to their names F. R.S. 
1 might, perhaps, have sought an asylum 
for this paper in the ‘ Transactions of 
the Royal Society ;” but as I have not, 
and as, after all, utility ought to be our 
chief object in writing, I am inclined to 
think that your channel of communica- 
tion has many advantages over those of 
many learned societies, whose large and 
expensive volumes must necessarily be 
restricted to very few hands, 
The mode in which sperma ceti is ob- 
tained from the whale I do not mean to 
describe, having had no satisfactory in-’ 
formation upon the subject; but it is, I 
have been told, got from every part of 
the fish, together with the ol, but more 
especially the head. It is usually 
brought home in casks; and, in some 
cases, has so little oil mixed with it as to 
obtain, in commerce, the denomination 
of kead-mutter ; obtained, in all proba- 
bility, from the head. 1t is of the con- 
sistence of a stiff ointment, of a yellowish’ 
colour, and not tenacious, Besides’ the 
head-maiter, there is also a quantity of 
sperm obtained from the oil by filtration, 
Indeed, in ali good sperma ceti lamp 
oil, which is not transparent, particles of 
the sperm may be seen floating, Having, 
_ your head-matter, or fiitred Sperm, in 
order 
The parts of the fish | 
