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premifing, that, where a continuity
of tranfmiffion appears to have taken
place, arifing from the intercourfe
of nations with each other; and
where the words are the fame, the
grammatical construction, and other
minute peculiarities of compofition
much alike, in two languages, thefe
languages are of the fame texture:
and that alphabetical compofition,
attended by these circumstances of
refemblance, muft flow from one
fource: efpecially, if the difference
in the alphabetical marks of thefe
two languages fhould be no objec-
tion, but may be accounted for up-
on reasonable principles.

"It will be readily allowed then,
I prefume, that no modern Euro-
pean nation, exclufive of the Turk-
ith empire, indebted to the Greeks
and Arabians, feparately invented
alphabetical writing: we all de-
rived, without any doubt, this art
from the Romans. The Romans
never laid claim to the difcovery
they afcribed all their literary ad-
vantages to the Greeks. This ac-
complished people acknowledge,
with one voice, to have received
the art from the Phoenicians; who,
as well as their colonists the Car-
thaginians, are known by the learn-
ed to have spoken the Hebrew lan-
guage, or a dialect scarcely vary
ing from the original. The Cop-
tic, or Egyptian, wears the ex-
actest resemblance in the majority
of its characters to the Greek
they, therefore, must be referred in
all reafon to the fame origin. The
Chaldee, Syriac, and later Samari-
tan, are dialects of the Hebrew,
without any confiderable deviation,
or many additional words. The
Æthiopic differs more from the He-
brew, but still less than the Arabic.
Thefe languages, however, not-
withstanding fuch deviations, have
iffued from the fame ftock; as the

fimilarity of their formation, and the numberlefs words, common to them all, demonftrably evince: and the Perfic has a close affinity to the Arabic. Alterations would naturally be introduced, proportionate to the civilization of the feveral poffeffors, and their feparation from the other nations: and this will account for the fuperior copiousness of fome above the reft. So then, not to determine which was the more ancient language, the Hebrew, Syriac, or Arabic, a question of no importance on this occafion; all the languages in use amongst men, that have been conveyed in alphabetical characters, have been the languages of people, connected ultimately or immediately, with thofe who have handed down the earlieft fpecimens of writing to pofterity. And when the languages of the eastern nations are fo fimilar

when fo curious an art would be, in all probability, the first improvement communicated by one people to another is it not morally certain, that alphabetical writing originally centered in one people? For length of time has deprived us of exprefs hiftorical testimony in this cafe.

"Indeed, this propofition feems to be fufficiently afcertained by another argument; that is from the fameness of the artificial denominations of the letters in the Oriental, Greek, and Latin languages; ac companied too by a fimilar arrangement: Alpha, Beta, and so on.

"But in oppofition to this evidence, fome will argue against all poffible admiffion of our conclufion, by alledging the entire diffimilarity of characters employed by the ancients to difcriminate their letters. "Why should not one nation, it will be urged, adopt from the other the mode of expreffing the art, as

well

the impreffion on the leaf was made in fuch a way as to affect the petiolus, the motion took place. When, therefore, I wanted to confine the motion to a fingle leaf, I either touched it fo as only to affect its own petiolus, or, without meddling with the leaf, touched the petiolus with any small-pointed body, as a pin or knife.

66

By compreffing the univerfal petiolus near the place where a partial one comes out, the leaf moves in a few feconds, in the fame manner as if you had touched the partial petiolus.

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Whether the impreffion be made by puncture, percuffion, or compreffion, the motion does not instantly follow generally feveral feconds intervene, and then it is not by a jirk, but regular and gradual. Afterwards, when the leaves return to their former fituation, which is commonly in a quarter of an hour or lefs, it is in fo flow a manner as to be almost imperceptible.

"On fticking a pin into the univerfal petiolus at its origin, the leaf next it, which is always on the outer fide, moves firft; then the first leaf on the opposite fide, next the fecond leaf on the outer, and so on. But this regular progreffion feldom continues through out; for the leaves on the outer fide of the pinna feem to be affected both more quickly, and with more energy, than thofe of the inner, to that the fourth leaf on the outer fide frequently moves as foon as the third on the inner; and fometimes a leaf, efpecially on the inner fide, does not move at all, whit thofe above and below it are affected in their proper time. Some times the leaves at the extremity of the etiolus move fooner than fe

veral others which were nearer the place where the pin was put in.

"On making a compreffion with a pair of pincers on the univerfal petiolus, between any two pair of leaves, thofe above the compreffed part, or nearer the extremity of the petiolus, move fooner than thofe under it, or nearer the origin; and frequently the motion will extend upwards to the extreme leaf, whilft below it perhaps does not go farther than the nearest pair.

If the leaves happen to be blown by the wind against one another, or against the branches, they are frequently put in motion; but when a branch is moved gently, either by the hand or the wind, without striking against any thing, no motion of the leaves takes place.

"When left to themfelves in the day-time, fhaded from the fun, wind, rain, or any disturbing caufe, the appearance of the leaves is different from that of other pinnated plants. In the laft a great uniformity fubfifts in the refpective potition of the leaves on the pinna; but here fome will be feen on the horizontal plane, fome raised above it, and others fallen under it; and in an hour or fo, without any or der or regularity, which I could obferve, all thefe will have changed their respective positions. I have feen a leaf, which was high up, fall down; this it did as quickly as if a strong impreffion had been made on it, but there was no caufe to be perceived.

"Cutting the bark of the branch down to the wood, and even separating it about the fpace of halt an inch all round, fo as to stop all communication by the veffels of the bark, does not for the first day affect the leaves, either in their pofition or their aptitude for motion.

writing. The experiment has been fairly made upon the ingenuity of mankind for a longer period than that which is fuppofed to have produced alphabetical writing by regular gradations; and this experiment determines peremptorily in our favour.

"The Chinese, a people famous for their difcoveries and mechanical turn of genius, have made fome advances towards the delineation of their ideas by arbitrary figns; but have nevertheless been unable to accomplish this exquifite device: and after fo long a trial, to no purpofe, we may reasonably infer, that their mode of writing, which is growing more intricate and voluminous every day, would never terminate in fo clear, fo comparatively fimple, an expedient, as that of alphabetical characters.

"The Mexicans, alfo, on the new continent, had made fome rude attempts of the fame kind, but with lefs fuccefs than the Chinese.

"We know alfo, that hierogly phics were in ufe among the Egyptians, pofterior to the practice of alphabetical writing by the Jews: but whether the epiftolography, as it is called, of the former people, which was in vogue during the continuance of hieroglyphics, might not poffibly be another name for alphabetical writing, I will not take upon me to decide.

"Now what will our adverfaries reply to this? They will pertinacioully maintain, that alphabetical writing is a human invention: and yet all thofe nations, who have been converfant with this expedient, are difcovered to have derived it from the fame original, from fome one people in the Eaft, whofe means of attaining it we cannot now find out; but are compelled to conclude from analogy, and the experience 1785.

of other nations, that their imagi nation, as it was not more fertile, was not more fuccefsful, than that of their neighbours.

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Again where large commu nities have flourished for ages, but unconnected with thofe countries which enjoyed this advantage, their own folitary exertions were never capable of effecting this capital difcovery. Is it poffible for prefumptive evidence to be more fatisfactory than this?

IV. Laftly, we will confider the argument upon which the commonly received fuppofition entirely depends: that is, the natural gra dation through the feveral fpecies of fymbols, acknowledged to have been in ufe with various people, terminating, at laft, by an caly tran fition, in the detection of alphabetical characters. I cannot fee this regularity of procefs, this cafe of tranfition, fo clearly as fome others appear to do; but let every one determine for himself from the con templation of the feveral stages of emblematical rep efentation.

"1. The firit method of embo. dying ideas, would be, by drawing a reprefentation of the objects themfelves. The imperfection of this method is very obvious, both on account of its tedioufnefs, and its inability of going beyond external appearances, to the abstract ideas of

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[164] EXPERIMENTS on the LOSS of WEIGHT in BODIES,

in fhewing the lofs of weight In ice on being heated.

"The beam I made ufe of was fo adjusted as that, with a weight between four and five ounces in each scale, part of a grain I made a difference of one divifion on the index. It was placed in a room, the heat of which was 37 degrees of Fahrenheit's thermometer, between one and two in the afternoon, and left till the whole apparatus and the brafs weights acquired the fame temperature.

for about a minute, I found it began to lofe weight, on which I immediately took it out, and placed it at a distance from the beam. I alfo immediately plunged a ther mometer in the freezing mixture, and found the temperature 10 degrees; and on putting the ball of the thermometer in the hollow at the bottom of the glafs vessel, it fhewed 12 degrees. I left the whole for half an hour, and found the thermometer, applied to the hollow of the glafs, at 32°. Every "A glass globe, of three inches thing now being at the fame temdiameter nearly, with an indenta- perature, I weighed the glafs contion at the bottom, and a tube at taining the ice, after wiping it carethe top, weighing about 451 grains, fully, and found it had loft and had about 1700 grains of New- five divifions; so that it weighed river water poured into it, and was, all but one divifion, more than hermetically fealed, fo that the when the water was fluid. whole, when perfectly clean, weighed 2150 of a grain exactly; the heat being brought to 32 degrees, by placing it in a cooling mixture of falt and ice till it just began to freeze, and fhaking the whole together.

"After it was weighed it was again put into the freezing mixture, and let stand for about 20 minutes; it was then taken out of the mixture part of the water was found to be frozen; and it was carefully wiped, firft with a dry linen cloth, and afterwards with dry washed leather; and on putting it into the scale it was found to have gained about the part of a grain. This was repeated five times: at each time more of the water was frozen, and more weight gained. In the mean time the heat of the room and apparatus had funk to the freezing point.

"When the whole was frozen, it was carefully wiped and weighed, and found to have gained of a grain and four divifions of the index. Upon standing in the fcale

"I now melted the ice, excepting a very finall quantity, and let the glafs veffel exposed to the air in the temperature of 32 degrees for a quarter of an hour: the little bit of ice continued nearly the fame. I now weighed it, after carefully wiping the glafs, and found it heavier than the water was at first, one divition of the beam. Lastly, I took out the weights, and found the beam exactly bas lanced as before the experiment.

"The acquifition of weight found on water's being converted into ice, may arife from an increase of the attraction of gravitation of the matter of the water; or from fome fubftance imbibed through the glafs, which is neceffary to render the water folid.

"Which of thefe pofitions is true may be determined by form ing a pendulum of water, and another of ice, of the fame length, and in every other refpect fimilar, and making them fwing equal arcs. If they mark equal times, then certainly there is fome matter added

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to the water. If the pendulum of ice is quicker in its vibrations, than the attraction of gravitation is increased. For there is no pofition: more certain, than that a fingle particle of inanimate matter is perfectly incapable of putting itself in motion, or bringing itfelf to reft; and therefore that a certain force applied to any mafs of matter, fo as to give it a certain velocity, will give half the quantity of matter double the velocity, and twice the quantity, half the velocity; and generally a velocity exactly in the inverse proportion to the quantity of matter. Now, if there be the fame quantity of matter in water as there is in ice, and if the force of gravity in water be

I

part lefs than in ice, and the pendulum of ice fwing feconds, the pendulum of water will lofe of a fecond in each vibration, or one fecond in 28000, which is almoft three feconds a day, a quantity eafily measured.

I fhall just take notice of an opinion which has been adopted by fome, that there is matter abfolutely light, or which repels instead of attracting other matter. I confefs this appears abfurd to me; but the following experiment would prove or difprove it. Suppofing, for initance, that heat was a body, and abfolutely light, and that ice gain ed weight by lofing heat; then a pendulum of ice would fwing through the fame arc in lefs time than a fimilar pendulum of water; for the fame power would not only act upon a lefs quantity of matter, but a counter-acting force would also be taken away.

"Till the experiment of the pendulum can be made, or fome other equally certain be fuggefted and made, it would be wafting time to enter into conjecture about the

caufe of the gain of weight in the converfion of water into ice in a glafs veffel hermetically fealed.

"Ifhall only obferve, that heat certainly diminishes the attractions of cohefion, chemistry, magnetifm, and electricity; and if it should alfo turn out, that it diminishes the attraction of gravitation, I should not hesitate to confider heat as the quality of diminution of attraction, which would in that cafe account for all its effects.

"We come, in the next place, to take notice of the fecond part of the experiment, viz. that the ice gained an eighth part of a grain on being cooled to 12 degrees of Fahrenheit's thermometer. In this cafe, a variation may arife from the contraction of the glafs veffel, and confequent increase of specific gravity in proportion to the air. But it is unneceffary to obferve, that this would be fo very small a quantity as not to be obfervable upon a beam adjusted only to the degree of fenfibility with which this experiment was tried. In the fecond place, the air cooled by the ice above the fcale becoming heavier than the furrounding atmosphere, would prefs upon the fcale downward with the whole force of the difference. If a little more than half a pint of air was cooled over the fcale to the heat of the ice and glafs containing it, that is, 20 degrees below the freezing point, the difference, according to general Roy's table, would have been the eighth part of a grain, which was the weight acquired; but the air within half an inch of the glafs veffel being only one degree below the freezing point, I cannot conceive, that even an eighth part of a pint of air could be cooled over the icale to 20 degrees below the freezing point; nor that the whole dif

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