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The Philosophical transactions of the Royal society of London, from their commencement in 1665, in the year 1800 (Volume 8) online

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On the following case Dr. G. observes, that the reason of the child's being
able to abide so long under water was pretty evident: the child, most likely,
was infirm, weak, and sickly, from the time of her birth, so that the foramen
ovale was not grown up. He remembered about 3 years before to have seen a
subject, a woman, 80 years old, who had the foramen ovale so large, that one
might easily thrust the middle finger through it ; but she was attended with the
above-mentioned circumstance, that is, she never enjoyed a moment's health
in her life.

May l6, 1737, Rebecca Yates, of Billson near Market-Bosworth in Leices-
tershire, had a daughter about 3 years of age, that fell into the milldam at the
head, near the mill-wheel; and, by the force of the stream, was drawn under
the water to the wheel, with her legs forwards ; one of her legs went under
the mill-wheel, and by reason of the nearness of the wheel to the floor of its
water-way, the bulk of the child's leg stopped the wheel from moving at
all. The sudden stopping of the mill so much surprised the miller, that he
went immediately, and let down the shuttle; but finding it would not go quite
down, he came up again into the mill, and looked both above and below, to see
if he could find out the cause; then went and drew up the shuttle, and let
it down again ; but as the gate would not shut quite down, he could not as yet
find out the cause of his mill standing still; for which reason he went backwards
and forwards between the shuttle and mill-room, for 8 or 10 times, before he
found out the cause; but at last he drew the shuttle quite up, by which means
the force of the water drove the child from under the shuttle; then he put the
shuttle quite down, and thereby discovered the child with her leg under the
wheel, and lying on her face. The first word she spoke was, help me, which
she repeated 3 times; the miller left her arm for some other person to hold her,
while he endeavoured to remove the wheel, so as to get out her leg; and then
she said again, for God's sake help me out, if you can: she spoke very briskly,
after she was put to bed. But the mill-wheel had torn away all the shin, mus-
cles, sinews, and tendons, of her leg, quite to the bone, and stripped them
down to her heel ; besides, the shuttle was drawn up and let down on the small
of her back several times. The child lived from Monday till Friday, and then
died of her wounds and bruises. The whole time of her being under water,
which was at the depth of 4i feet, was near 15 minutes.




The Case of Mr Cox, Surgeon at Peterborough, who fell into a Pesti-
lential Fever on tapping a Corpse lately dead of a Dropsy, drawn up by hivi -
self, and read before the Peterborough Society, Sept. 1, I736. N° 454, p. 168.

An elderly gentlewoman, labouring under a dropsy about 12 months, under-
went the operation of tapping 4 several times, by which 35 quarts of liquor
were discharged; and dying at last of the distemper, Mr. C. was desired by her
friends to let out the water that was then contained in the abdomen, as well to
preserve the corpse the longer from putrefaction, as to prevent an annoyance
to the company at the time of her funeral. — Yet notwithstanding this was done
within a few hours after death, the included humours were become so putrefied
as to discolour the external parts with a green and livid hue. The liquor itself
was green, and somewhat thicker than new milk; in smell more fetid and of-
fensive than what he ever met with, and so sharp and acrimonious in its nature,
as deeply to corrode a silver canula, through which it passed. And what showed
it to be highly malignant, may be judged of from the following circumstances.

The night after the operation, he was somewhat restless and uneasy, and
the next day afflicted with small tremors, and an unusual lassitude; in about 3
days after, several angry pustules arose on his hands and fingers, and on every
place where the least drop of water fell ; some of which coming to matter,
went off" soon; those which did not, continued painful, and remained much
longer. The thumb of his right hand, and middle finger of his other, were
affected more severely than any other part, the pain more exquisite, the swell-
ing more hard and large, and of a red dusky complexion. This was about the
6th day of his illness, and though the strongest suppuratives were made use of,
yet they failed of the desired success, the pains being continual. Being per-
suaded from the great pulsation and heavy pains, that matter must lodge either
under or on the periosteum, an incision was made to the bone, by which only
two or three drops of matter were discharged. It was expected this small dis-
charge might in some measure mitigate his pain, but it did not; the same
evening, that pain he at first complained of was changed into universal convul-
sions, and the oppression on the vitals so great, as to threaten immediate

The intentions of cure were to fortify the heart with cordials, to enable it
to resist and throw out the malignity, and to bring the sores to a plentiful
digestion .

The first was treated with the highest alexipharmics; the latter, as at first,
with strong suppuratives; this being about the 8th day of his illness, and the




convulsions continuing, with an unequal and low pulse, and as there was little
appearance of matter, blisters were applied, as near to the parts affected as pos-
sible, in order to make a revulsion from the heart, and throw oft" the morbid
matter by the wounds. In about 3 days this point was gained, the convulsions
began to abate, and the wounds to digest; in 4 more, he found a cessation of
symptoms, except a faintness and lowness of spirits, which hung upon him for
a great while after, which pestilential fevers are known always to leave behind

He supposes he might receive this infection, as much by inspiration as con-
tact; for some of his assistants, who were in the room only, and never touched
a drop of the liquor, found themselves much disordered, and afterwards broke
out with red and livid eruptions; which sufficiently showed, that not only the
liquor itself, but the effluvia also, were in the highest degree subtle and ma-

The Variation of the Magnetic Needle, as observed in three voyages from London
to Maryland. By Waller Hoxton. N" 454, p. J 7 1 •

N. B. The longitude is reckoned from the Lizard.

The first Voyage in 1732.

Latitude Longitude Variation

north west west

39° 53' 27° 16' 12° 0'

37 49 27 45 14

35 19 39 20 13

32 40 50 27 8

34 40.

35 4.


,.56 6

. . 65 4

36 50 4


36 11 56 20 . . ... 9 22

34 52 53 6 17

34 33 52 6 15

34 45 51 6 5

34 36 50 6 23

36 49 30 7 37

37 20 48 9 23

38 4 48 20 10

39 27 47 40 10 23

40 8 45 40 10 38

40 30 45 13 4

42 32.^ 42 20 11 43

42 40 42 12 39

43 27 40 20 13 24

43 32 39 50 13 42

49 48 9 \6 30

The second Voyage 1733.

48 12 3 18 18

46 7 4 30 l6 35







44° 4'. . .

,... 7°

0. ..

. . . 16° 22'

42 17 . . .

... 9


. . . 16 36

40 . . ,

,. .12


...15' 38

38 5 . . .



...14 51

37 36 . . ,



. . . 13 24

36 32...

. ..15


...13 17

36 16...

. . . 16



34 2 . . .



...11 34

34 4 . . .



... 9 51

35 6 . . .


33 . . .

. . . 10 28

35 12 31 38 9 48

34 23 31 22 10 23

33 34 32 25 8

30 19 31 26 7

29 17 31 11 6

32 24 37 55 6

32 50 38 35 10 36

32 11 40 23 11

31 19 41 9 6 42

32 25 43 5

34 5 47 20 8 49

33 45 49 24 10 45

35 1 54 10 .

34 54 4 .

33 41 54 .

33 51 : 55 0.

34 59 60 .

36 32 . .

. 5

. 6

. 7

59 30 7


8 33
5 53

XX 2



[anno 1739.







37" 1'. .

....61° 10'...



37 5..

....66 22...



36 53..

....66 40...

... 4


36' 36 . .

....66 40 . . .


38 9..

57 40 . . .


38 48 . .

....55 50 . . .


42 13 . .

43 48 . . .


44 21..

....33 17...



45 46..

28 17...



49 51..

. . off Plymouth.



50 20 . .

. . oft" Portland .


Tie third Voyage, 1734.

39 53 . .

.... 6 37...



37 50 . .

.... 6 40...


36 58 . .

10 30 . . .


34 56 . .

13 0...



33 33 . .

....16 10...

.. 12


33 9..

...17 38...

.. 9


32 44 . .

...18 6...

.. 9


Latitude Longitude Variation

north west west

31" 39' 20" 13' 9° 49

30 55 .
30 17 .

.22 53 9 6

.25 26 8 39

.27 14 7 56

30 1 ..

30 1 27 54 6

. . 30 20 7

..33 12 8

29 55 . .

29 57 . .

29 51..

28 55 . ,

29 8 40 7

31 10 44 46 8

31 7 46 45 4




30 42 49

30 29 49 48

30 31 52

30 18 53

30 23 55

30 58 57 30 .

37 9 -

37 37 5

39 28 5 23

4 40
4 49
4 45
4 22
4 52


.68 4 50

Some Thoughts and Conjectures Concerning the Cause of Elasticity. By J. T.
Desaguliers, LL.D. F.R.S. N° 454, p. 173.

Attraction and repulsion seem to be settled by the great Creator as first
principles in nature ; that is, as the first of second causes; so that we are not
solicitous about their causes, and think it enough to deduce other things from
them. If elasticity was admitted as a first cause ; as it is by some, it is thought
we should admit of too many principal causes in nature ; which is contrary to
the rules of good philosophy. Philosophers therefore have endeavoured to de-
duce elasticity from attraction, or from repulsion, or from both. It is observed,
that the same particles that repel each other strongly, will attract other particles
very strongly ; as apppears by many chemical solutions, especially by the
alternate solution and precipitation of metals in acid menstruums. Dr. Hales
has proved this many ways, in his vegetable statics and haemastatics. The
elasticity of air seems to consist wholly in the repulsive power of its particles,
which do not touch one another while the air is in its elastic state ; and if
those particles be brought nearer and nearer together, the efi^ect of their re-
pulsive force will increase, the air's elasticity being always proportionable to
its density by compression, which property will be preserved, though com-
pressed air be kept a year or two ; notwithstanding, Mr. Hawksbee, in his
Physico-mechanical Experiments, says, that air will lose part of its spring by
being very much compressed. But the air with which he tried it, must have
been filled with moist vapours ; and it is well known, that the steam of liquors
will lose its elasticity, especially where its heat decays. Dr. D. has kept several



wind-guns, strongly charged, for half a year together, in which the air had lost
none of its elasticity : others have found the air as strong after a year ; and a
person of credit has asserted, that a wind-gun having been laid by and forgotten
for 7 years, when it was found, discharged its air as many times, and with as
much force, as it used to do. Now, though air, compressed by any external
force, does always increase in elasticity, as it diminishes in bulk ; yet it may,
by fermentation, diminish its bulk very much, without gaining any more elasti-
city: for if another fluid, whose parts repel one another, but attract the parts of
air, be mixed with it, the repulsion of any two particles of air will be diminished,
in proportion as a particle of the other fluid, insinuating itself between them, at-
tracts them towards itself on either side. The same <;hing will happen to the
other fluid, in respect of the particles of air, which mixing with its particles,
do in the same manner destroy their repulsion. Thus, if we allow an attraction
strong enough between the parts of two elastic fluids, it is possible, that by
fermentation a solid may be made out of two elastic fluids, which would have
still continued fluid without such a mixture. We are taught by chemistry, to
mix fluids together, which immediately coalesce into a solid. When brimstone
matches are burning, the effluvia of the sulphur repel each other to great dis-
tances, as may be known by the sulphureous smell. Now, though these par-
ticles repel each other, they attract the air very strongly, as appears by the fol-
lowing experiment.

Take a tall glass receiver, closed at top, holding about 4 quarts of air ; and
having put its open end over a bundle of brimstone matches on fire, standing
up in the middle of a large dish with water in it, to keep the air from coming in
at the bottom of the said receiver, you will observe, that not only as soon as the
matches are burnt out, but a good while before, the air, instead of being ex-
panded by the flame of the brimstone, will retire into less compass, the water
beginning to rise from the dish up into the receiver, and continuing so to do
till some time after the matches are burnt out ; so that there will be in the
receiver only 3 quarts of air, instead of 4, more or less, in proportion to the
quantity of brimstone burnt. And this plainly happens by some of the effluvia,
or little parts of the sulphur, attracting some of the particles of the air, so as to
make an unelastic compound, that precipitates into the water. If the elasticity
of the air is quite lost when the repulsion of its particles is taken oft', or suffi-
ciently counteracted, it must follow, that its elasticity depends on repulsion ;
and that this is often the case, appears by a great immber of Dr. Hales's ex-,

The doctor took a cubic inch of mutton-bone, and having put it into his
gun-barrel retort, he distilled out of it 200 or 300 cubic inches of air, inta
a large glass bottle, the weight of which air, together with the ashes of the


bone left, weighed as much as the whole quantity of bone did at first. Now
the air had been confined in that bone, together with many sulphureous par-
ticles, in such a manner, that the mutual attraction of the sulphur and the air
had alternately destroyed each other's repulsive force, and brought those sub-
stances into a little compass ; but the fire in the distillation separated them
from each other, so as to restore them in a great measure, to their usual elas-
ticity. This appeared by bringing a candle near the mouth of the bottle that
held this revived air ; for every time the candle was brought near, the air took
fire, and flashed out of the bottle with a sulphureous smell.

The air may be consolidated in many hard bodies, so as to be there quite
void of elasticity, and there do the office of a cement, till by the action of fire,
or some particular fermentations, it is again restored to its perfectly elastic state.
This is the meaning of Dr. Hales's words, when he says, that some bodies ab-
sorb, and others generate air ; and the same bodies do sometimes absorb, and
at other times generate air. He found more or less air in almost every solid
substance that he tried ; but, what was most remarkable, he found that the
calculus humanus, or stone taken out of a man's bladder, was made up of above
half its weight of air.

Some have endeavoured to solve elasticity by attraction only ; as for example
— If the string a b, fig. 7, pU 7, be considered as made up of particles lying
over one another in the manner represented at a d b ; it is plain, that if the
point D be forcibly brought to c, the parts will be drawn from each other ; and
when the force, that stretched the string, ceases to act, the attraction of co-
hesion, which was hindered before, will take place, and bring back the string
to its former length and situation, after several vibrations. Now, though this
seems to agree pretty well with the phaenomena of a string in motion, it will by
no means solve the elasticity of a spring fastened at one end, and bent either
way at the other, like a knife or sword-blade, as in fig. 8. For if such a spring
be bent from A to a, the particles on the side c, which now becomes convex,
will be farther asunder at f, while the particles at d, carried to the concave
part E, will come closer together : so that the attraction, instead of making
the spring restore itself, will keep it in the situation in which it is, as it hap-
pens in bodies that have no elasticity, where perhaps only attraction obtains.
Thus a plate of lead, a plate of copper, and a plate of soft iron, stands bent.

But the most probable way of accounting for the elasticity of springs, is to
consider both a repulsive and an attractive property in the particles, after the
manner of the black sand, which is attracted by the load-stone, and has been
shown, by Musctienbroek, to be nothing else but a great number of small


Let US suppose a row of round particles touching one another only in the
points c in a line from a to b, fig. Q. It is plain, from what philosophers have
shown concerning the attraction of cohesion, that on the least shake or alteration
of the position of a straight line, these particles will run together, and form a
sphere, in which the globules will have more points of contact. But if these
particles have poles like magnets, in the opposite places marked n s, so that all
the poles n, n, n, &c. repel one another ; and all the poles s, s, s, &c. likewise
repel one another, the line a b will continue straight ; for if by any force the
same line b a be put into another position, as into the curve b a, then the poles
n, n, &c. being brought nearer together, while the poles s,s, &c are further
asunder, will repel one another more strongly, and so hinder the globules from
running together towards the concave part ; and the spring, left to itself, all
this while supposing one end, as b, b, or |3, fixed, will restore itself, throwing
its end a back to A, and so on to a, by the first law ; then, being in the po-
sition « (3, the poles s, s, &c. are brought nearer together, whose repulsion, thus
increased, throws back a to a, and so on forward, the line of particles perform-
ing several vibrations round b.

May not a spring of steel, or other springs, consist of several series of such
particles, whose polarity and attraction acting at the same time, will show
why such bodies, when they have been bent, vibrate, and restore them-
selves ?

If we take a plate of steel, and make it so hot till it looks white, and then
immediately quench it, we thereby fix the metal in a state very near fluidity,
so that the particles which the fire had almost brought to roundness, have but
a very small contact ; as appears by the fragility of the steel thus hardened,
which breaks like glass, and has a short grain. Steel, thus hardened, is highly
elastic ; for what workmen call hard, is the most elastic ; as appears by the
congress of high-hardened steel balls, which return, in their rebound, the
nearest to the place we let them fall from ; and, next to glass, have the quickest
elasticity of any thing we know.

That we may not be thought to have given an imperfect account of the elas-
ticity of a steel spring, because such a one as we have described wants tough-
ness, and will immediately fly, when bent to any degree ; we must beg leave
to consider further the properties of the round particles, or little spheres, of
steel, in which we have supposed a polarity.

Let us suppose a B, fig. 10, to be two little spheres or component particles
of steel, in which, at first, we will suppose no polarity, but only an attraction
of cohesion. Then, whether the particles have their contact at c, d, e, n, or
at i, t, s, their cohesion will be the same ; and the least force imaginable will


change their contact from one of those points to another; because in the roll-
ing of these little spheres, they do not come into more or less contact, in one
situation than another. But if we suppose the point n in each spherule to be a
pole, with a force to repel all the other points n in any other spherule, and
likewise s another pole, repelling the other points s ; the spherules will cohere
best, and be at rest in that position, where the points c, c, are in contact, and n
and s at equal distances on either side. For if the spherules be turned a little,
so as to bring the points d, d, into contact, as in fig. li, the poles, n, n, being
brought nearer, act against each other with more force than the points s, s,
which are now farther off, and consequently drive back the spherules to the
contact at c c, beyond which continuing their motion, they will go to SS,
fig. 12, and so backwards and forwards, till at last they rest at cc, which we
may call the point of equilibrium for rest in a spring. Now there are, besides
this, two other points of equilibrium, beyond which the spring may break,
which are the points e, e, towards n, and f, f, towards s; see fig. 13, that is,
when the spherules have their poles n, n, brought very near together, the mu-
tual repulsion increases so, that the attraction at the contact is not able to hold
them, and then they must fly asunder, the spring breaking. We suppose the
points e, e, to be the points of contact, beyond which this must happen ; but
that if the contact be ever so little short of it, as between e and d, the spherules
will return to their contact at c, after some vibrations beyond it, as has been
already said. This is the reason why he calls e, in one of the spherules, and
its correspondent point £, on the other side c, the points of equilibrium ; for if
the spring be bent towards a, fig. Q, so that the spherules, like a and b, fig. 13,
touch beyond e, the spring will break. Likewise if the spring be bent the
other way, till the spherules touch beyond e, then it will break the other way.
Now when the spherules touch at e,e, or at f, s, the spring is as likely to return
to its first position as to break ; for which reason he has called the points e and
I, points of equilibrium, as also, having known by experience, that a spring
left bent to a certain degree, has, after some time, broke of itself.

From all this it appears, that spherical particles will never make a tough
spring ; therefore the figure of the particles must be altered, in order to render
it useful ; and this is what is done in bringing down the temper of the hard
steel, and letting down a spring, as it is called. What change ought to be
made in the particles, we shall first show ; and then consider how far that is
done by those who make springs.

If the parts supposed globules, as in fig. Q, are now flattened at c, where the
contact is, so as to put on the shape n e dc Jt s, as in fig. 14, the contact will
be much increased, and reach from d to S, so that in bending the spring there


will still remain a great contact in the particles, and the points of equilibrium
for breaking, viz. o, e, above, and t, c, below, will be removed nearer to the poles
n, or s, than when the particles are round ; the consequence of which will be^
that the spring must be bent much further, to be in danger of breaking, than
in the former supposition ; as may be seen in fig. 15, where two particles being
opened about the point d as a centre, the attracting points c, c, and S, i, have
still some force to help to bring back the particles to their whole contact ; be-
cause, in this shape of the particle, the attracting points c, c, S, S, are removed
only in proportion to their distance from the angular point d ; whereas if the
particles had been spherical, and the line d S an arc of a circle, the attracting
points c, c, and i, i. would have removed from one another further than in pro.
portion to twice the square of the distance from d, as in fig. 11, and so have
afforded very little help for bringing back the particles to their contact. A row
of particles in the spring thus conditioned, is to be seen in the natural state at
BA, fig. 1 6, and bent at ba in the same figure. Here it is to be observed, that
if, in this figure of the particles, you would bend the spring to bring the par-

Online LibraryRoyal Society (Great Britain)The Philosophical transactions of the Royal society of London, from their commencement in 1665, in the year 1800 (Volume 8) → online text (page 40 of 85)