542 
D I V 
tioned, and was fastened to both. When the 
wood screw was fixed, and to be cast off 
tr ™} lts tube > the magazine was to be cast 
oil likewise by unscrewing it, leaving it hang- 
ing to the wood screw; it was lighter than 
the water, that it might rise up against the 
object to which the wood screw and itself 
were fastened. 
Within the magazine was an apparatus, 
constructed to run any proposed length of 
tune : it unpinioned a strong lock resembling 
a gun-lock, which gave fire to the powder, 
this apparatus was so pinioned that it could 
not possibly move till, by casting off the ma- 
gazine from the vessel, it was set in mo- 
tion. 
The skilful operator could swim so low on 
the surface ot the water as to approach very 
near a ship- in the night, without fear of being 
discovered; and might, if he chose, ap- 
proach the stem or stern above water with 
very little danger. He could sink very 
quickly, and keep at any depth he pleased, 
mid row a great distance in any direction he 
desired, without coming to the surface ; and 
when he rose to the surface, he could soon 
obtain a fresh supply of air, when, if neces- 
sary , fie might descend again, and pursue his 
course. 
~. Experiments made to prove the nature 
and use of a submarine vessel. The first 
experiment made was with about two ounces 
ot gunpowder, which were exploded four 
teet under water, to prove to some of the 
first personages in Connecticut, that powder 
would take fire under water. 
The second experiment was made with 
two pounds of powder, inclosed in a wooden 
boitle, and fixed under a hogshead, with a two- 
mch oak plank between the hogshead and 
the powder; the hogshead was loaded with 
stonea as deep as it could swim; a wooden 
pipe descending through the lower head of' 
the hogshead, and through the plank, into 
the powder contained in the bottle was 
primed with powder. A match put to the 
pruning, exploded the powder ; which pro- 
duced a very great effect, rending the 
plank into pieces, demolishing the hogshead 
and casting the stones and the ruins of the 
hogshead, with a body ot water, many feet 
into the air, to the astonishment of the spec- 
tators. This experiment was likewise made 
lor the satisfaction of the gentlemen above- 
mentioned. 
There were afterwards made many expe- 
riments of a similar nature, some of them 
with large quantities of powder; they all pro- 
duced very violent explosions, much more 
than sufficient for any purpose had in view. 
In the first essays with the submarine ves- 
sel, the inventor took care to prove its 
strength to sustain the great pressure of the 
incumbent water, when sunk deep, before he 
trusted any person to descend below the sur- 
face; and lie never suffered any person to go 
under water without having a strono- piece 
of rigging made fast to it, until he found him 
well acquainted with the operations neces- 
sary for his satety. After this he made him 
descend, and continue at particular depths 
without rising or sinking, row by the compass 
approach a vessel, go under her, and fix 
tne wood screw into her bottom, &c. until 
he thought him sufficiently expert to put anv 
design into execution. J 
D I V 
D I V 
of common ingenuity a ^kilfifi 'op era tor 0 ^ 3 £ avouraWe opportunity; 
the first employed was very EnSus and Y nT' 
made himself master of the business h„’i ! • 4 *. Other experiments made with a ele- 
ven sick in the campaKu OH776 at New KS h ° ^ *}****' In the > 1777 Mr, 
^ ork, before he had an opportunity^ m-ffe m ^- de , a;1 attem pt from a whale-boat 
use of his skill, and never ? aga “ st die Cerberus frigate, then king at 
health sufficiently afterwards "" , T Ilch ? r be { we * n Connecticut river and Sew 
3 Fvnp • , , L ? nd <? n > b y drawing a machine against her 
vessel Afil raen made Wlth a submarine Slde >, b ? ^earis of a line. The machine 
vessel. After various attempts to find an ope- | was oaded VVIth powder, to be exploded by a 
ins wish \ 1 i' .11 . r - mm- nrl' r . __ • r , . J 
-tor to his wish, Mr. HSl ^ X 
appeared more expert than the rest, from 
Ikcu \ ork to a fifty-gun ship, lying not far 
from Governor s-island. He went under the 
• llp , and attempted to fix the wood screw 
into her bottom ; but struck, as he supposes, 
a bar of iron, which passes from the rudder- 
V| ngc p and is spiked under the ship’s quarter 
Had he moved a few inches, which he iffio ■' 
babfvl?® ? lth r T ing ’ he w °uld P ?o- 
bably have found wood where he might have 
fixed the screw ; or, if the ship were sheathed 
v fill copper, he might easily.fiave pierced it ■ 
but not being well skilled iff the management 
t ,! eSSe ’ T att . em P tln g to move to ano- 
in v.c r ’ he ° st the slll P ; after seeking her 
in vain, for sometime, he rowed some dis 
, . V IV/ UV. tAUiyucu uv a 
O un-lock, which was to be unpinioned by an 
apparatus, to be turned by ‘being brought 
afongsidc of the frigate. This machine fell 
in v\ith a schooner at anchor, astern of the 
frigate, and concealed from his sffht By 
some means or other it was fired, and demo- 
lished the schooner and three men; and 
if. I ble "; 1 ie on] y one left alive overboard, who 
fit j was taken up very much hurt. 
After this he fixed several kegs under 
water, charged with powder, to explode, upon 
touching any thing, as they floated along with 1 
the tide ; he set them afloat in the Delaware 
above tne English shipping at Philadelphia! 
m December 1777. “ 1 was unacquainted,” 
says he, with the river, and obliged to cfe- 
pend upon a gentleman very imperfectly ac- 
quainted with ffinf „„ i ... * , 
tance 'and Z 1 p S . 0rae dis " B • u Pon a gentleman very imperfectly ac- 
tant, and did nnf arrive in-nil u • . i 
k v ^ contained in ; 1Ul 
bien fetal to the | tant, and did de-' 
,.„.TfL r rf Urn *™» ?W|> to New ! tamed some tone by frost: they advanced in 
IP v-f?rrr« i»a A'.-, i •» 
y * | t tut NUip LO .ffNCYV 
ffiriiirri h P assed P ear Governo^s-island, and ; the day-time in a "dispersed situation -mrl 
the i filnd" dl ! co . vered b y the enemy on ! under 'great disadvantages. One of 'them 
I ^ and* t 
)ur, the time the in- niVTCimr TT\r ,, 
had been cast off one hour, the time the 'in - 
ternal apparatus was set to run, it blew up 
with great violence. 1 
• Afterwards there were two attempts made 
m H udson s river, above the city, but they 
effected nothing. One of them was by 
the afore-mentioned person. In goffer 
towards the ship, he lost sight of her? and 
went a great distance beyond her: when he 
at ength found her, the tide ran so strong, 
that as he descended underwater for the ship’s 
bottom, it swept him away. Soon after this 
the enemy went up the river, and pursued 
the boat which had the submarine vessel on 
;°n f U , d sunk i,: with their shot. 
i hough, says Mr. Bushnell, “ I afterwards 
recovered the vessel, I found it impossible, 
at that time, to prosecute the design any fur- 
ther. I had been in a bad state of health 
from the beginning of my undertaking, and 
v as now very unwell; the situation of public 
affans was such that I despaired of obtain in 
the public attention, and the assistance ne- 
cessary. J was unable to support myself, 
and the persons I must have employed, had I 
proceeded. Besides, I found it "absolute- 
ly necessary that the operators should 
acquire more skill in the management 
of the vessel before I could expect success, 
which would have taken up some time, and 
made no small additional expence. I there- 
fore gave over the pursuit for that time, and 
DI\ ISIBILITY, that property by which 
j particles of matter in all bodies are ca- 
other ° 3 Se E aradoib OF disunion from eacii 
Soine philosophical writers have consider- 
? s -, a dlstluct property of matter 
itself, but it may with more propriety be 
considered as a property of extension ; for 
we can easily conceive that a given exten- 
sion may be divided into anv number of 
parts, let it be ever so great ; but it is by no 
means known whether matter is or is not 
capable of being divided ad infinitum, that 
is, without any limit. 
J hat a certain extension, as an inch, or 
any other length, be it ever so small, is ca- 
pable of infinite division, may be rendered 
evident by means of arithmetic or of geo- 
metry. VVe may take, for instance, the 
halves of the proposed extension, then the 
lalves of those parts, and so on without end - 
for if you proceed in this manner ever so 
ai, there will after all still remain the halves 
0 \ lhe ast Pfts. which may be also divided 
into other halves Ac. Again, suppose the 
line Al , Plate Miscel. fig. 55, to be the 
proposed extension. Through the extreme 
points of this hue draw two indefinite lines 
Eh and CD, parallel to each other. In one 
ot those lines, as EF, take a point L, and 
horn this point draw straight lines to any 
parts of the line D, every one of which 
