April 28, 1870 | 
NATORE 
657 
release a flint-lock at a determined period after it was 
set in motion. The machine was partly encased in cork, 
so that when charged with powder it was a little heavier 
than sea-water, and it was attached bya line to a box 
float, whereby it could be kept suspended at any particular 
depth. These torpedoes were carried in harpoon-boats, 
and connected by long lines with harpoons fired from 
small guns at the ship to be attacked. If the harpoon 
was successfully planted in the ship’s side, the torpedo 
was drawn into the water by the line, and this, as it ran 
out, released a pin from the torpedo, setting the clock- 
work in motion. The submerged torpedo was then 
supposed to drift into close proximity with the ship by the 
time the flint-lock caused ignition. Several French ships 
were attacked by means of these explosive machines— 
which, by the way, Fulton was the first to term /orfedoes 
—but although they were in some instances successfully 
exploded, the enemy’s vessels sustained no material 
injury, from the fact that the charges were immersed in 
too great a depth of water. Fulton’s drifting torpedoes were 
employed in a more simple form in an experiment made in 
October 1805, in the presence of the principal officers of 
the fleet commanded by Lord Keith, on which occasion a 
200-ton brig, the Vorothea, anchored for the experiment 
off Walmer Castle, was destroyed at one operation. The 
torpedo employed contained 180lb. of powder, and was 
suspended at a depth of fifteen feet ; it was simply allowed 
to drift with the tide against the hulk, the clockwork which 
regulated the explosion being timed to run eighteen 
minutes before the machine was cast adrift. 
The torpedoes made use of by the Russians in the 
Baltic in 1855, were mechanical self-acting machines, 
containing charges of from 8lb. to 1olb. of powder ; they 
were constructed with some care and ingenuity, and if 
they had been but of larger size, their existence would 
have greatly jeopardised the safety of our ships. The 
machines were conical in form, and were so arranged as 
to explode on being struck by a passing vessel, the blow 
causing the fracture of a glass tube containing sulphuric 
acid, which, falling upon a tuft of cotton wool saturated 
with chlorate of potash, sulphur, and sugar, at once ignited 
the charge. 
But it was not, as previously stated, until the subject of 
torpedoes was seriously taken in hand by the Americans 
during the recent war, that torpedo-warfare assumed a 
grave and wide-spread importance. In the hands of the 
Confederates especially, the applications of submarine 
mines to warlike purposes were very carefully studied, and 
with such marked success, that, according even to the 
official despatches of the Federals themselves, twenty-five 
ships are admitted to have been destroyed. In the first 
instance mechanical torpedoes only were used, such, viz., 
as exploded by means of percussion arrangements fitted 
on the outside, or by a drifting line attached to a trigger, 
but these were afterwards succeeded to some extent 
by machines ignited at will from the shore by electri- 
city. The latter were, in the opinion of Admiral Porter, 
of inferior value, from the fact of their ignition not being 
effected at the proper time; and the gallant officer re- 
ports, that on one occasion he safely ran the gauntlet 
through a channel bristling with these machines, by simply 
sending forward as pioneer a sham J/onz¢or built of logs, 
and furnished with an imitation turret, which passed with- 
out damage over several torpedoes exploded at her, and 
was afterwards followed by the fleet unharmed. 
Consequent upon the successful employment of torpe- 
does by the Confederates, the Federals turned their 
attention more closely to the matter, building a torpedo- 
boat especially for this kind of warfare, and reconstructing 
six Monztors for the same purpose. 
The perfection to which submarine mines have been 
brought up to the present time; and the various methods 
adopted for applying electricity to their ignition, will form 
the subject of the second part of this paper, 
THE DEEP-SEA SOUNDINGS AND 
GEOLOGY 
OME little time ago an eminent geologist, Professor 
Giimbel of Munich, applied to Sir Roderick Murchi- 
son for specimens of the Deep-sea Soundings which 
have lately been the subject of so much discussion. 
Sir Roderick mentioned Dr. Gimbel’s wish to me, 
and I immediately sent him a small quantity of North 
Atlantic mud from 2,350 fathoms, which had been pre- 
served in spirit. The following translation of a letter, 
dated April 18th, 1870, with which Dr. Gtimbel has 
favoured me, and which embodies the result of his 
researches hitherto, will, I am sure, be read with the 
greatest interest by geologists and biologisis. I may 
mention that I long since found coccoliths in the num- 
mulitic limestone of Egypt. T. H. HUXLEY 
Many thanks for sending me the specimen of mud obtained 
by the deep-sea dredge. I have already subjected it to 
searching investigation, and have obtained results, which have 
the most important bearing upon my other work. Although my 
inquiries are, at present, only commenced, it will possibly interest 
you to receive some information respecting them. I call the new 
kind of investigations which I have begun to carry out, ‘* Deep- 
sea investigations on the dry land ;” #¢., examinations of the 
different calcareous rocks, with reference to the share which 
the smallest organic forms, similar to those at present existing 
in thedeepsea, have had in their formation. When limestone is 
soft and earthy, traces of the smallest marine animals can be 
detected by triturating it in water. In chalk, for instance, from 
Palestine, I have convinced myself, in the most unequivocal 
manner, of the formation of the calcareous mass, for the 
greater part from your so-called coccoliths, besides Foraminifera, 
&c., which have long been known. Similar soft calcareous 
rocks are unfortunately rare in older formations. With these 
another process must be adopted. I started from the fact that 
in many of these calcareous rocks, the original calcareous 
portion of the organic beings is replaced by silica, and that 
hence in such rocks, by the separation of chert or flint, at 
least a part of the calcareous portion of the coccoliths and 
coccospheres might be replaced by silica. It was to be 
expected that the exterior form might suffer by this replace- 
ment, as, in fact, the chalk coccoliths have become materially 
different in their form from those of the existing deep-sea ooze. 
I found, in fact, by treating such a siliceous limestone with 
very dilute acetic or hydrochloric acid, in the fine mud which is 
left, an organic residuum corresponding to the coccoliths of the 
present day. Even in the Trenton limestone, and in a yellow 
limestone of the Potsdam series, corresponding minute bodies 
were to be recognised, although sparingly, presenting themselves 
amongst an incredible multitude of other minute particles 
of organic origin. The microscope discloses, like the tele- 
scope, in the vault of heaven, a new world of the smallest 
organic beings, respecting which, however, I must say nothing 
at present, but conhne myself to the coccoliths. These casts of 
coccoliths are found very sparingly. I explain this from the cir- 
cumstance that the silica is chiefly the result of the decomposition 
of large masses of organic material, especially of the larger testacea. 
LT obtained, however, important results by subjecting the deep- 
sea ooze, for which I am indebted to your kindness, to the action 
of the acids. ‘These with violent development of carbonic 
acid, dissolve the minute bodies of the coccoliths, of the 
coccospheres, and perhaps also those of Bathyéius (although of 
this IT am not quite sure), and there remain only certain 
peculiarly formed but very much changed portions of the cocco- 
liths as roundish discoidal flakes, the organic portion of the 
original coccoliths. In single isolated coccoliihs this change of 
form is difficult to follow, bunt this can easily be done in those 
which appear to be firmly bound up (enveloped ?) with a mass of 
the granular flakes (athydbzws?) ; and after the operation of the 
acid, can be again easily recognised in their exact position. 
Accompanying these coccoliths transformed by the action of acids, 
are countless little bodies extremely similar to those which can 
be obtained, in most cases, by dissolving siliceous limestone in 
acids. ‘ 
This is the first commencement of researches which I propose 
following up, with, I hope, important results; since thin 
sections are of no good in studying these minute forms, I 
cannot close these notes of the researches with which I am at 
