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388 Remarks on the Qualities and Properties of Amphibious Animals. disorder, and ran away. The master ordinary good or bad a&tion in the of the field, upon seeing this, flung space of three years, three months, his staff at him, which, by chance, three fortnights *, or three days. struck the Jackal, and so he was killed, and not the Deer. It is said, that Wherefore I repeat, Harmony be

tween the food and the feeder, &c. A man reapeth the fruit of any extra

Amphibiorum Virtutis Medicatæ Defensio. By John Hermann, Profesor of

Medicine, Canon of St Thomas, &c. Strasburg, 1787. 4to. T HIS is the first part of a work Thus, therefore, the amphibia of

that will be very acceptable to Hermann comprehend but a small the learned, especially to Naturalists: number of genera, to wit, the tortoise, the present fasciculus contains only some the toad, the frog, the lizard, the fac general remarks on the qualities and lamander, the flying lizard, and the properties of amphibious animals; the whole family of serpents. But if the Subsequent parts will comprehend a genera here are few, the species are particular account of the genera and exceedingly numerous ; the greater species in the class of amphibia ; and part of them too are little known, and it is there in particular that we shall it is very difficult to distinguish them find ourselves indebted for a great from one another. As M. Hernumber of new experiments and ob- mann is occupied in illustrating this servations, to Professor Hermann, one part of natural history, we are impaof the first naturalists in Europe. tient for the continuation of his work.

In the vulgar acceptation of the In this first section, which is the word amphibia, the otter, the beaver, subject of our review, the learned Prothe seal, and, in general, all the ani- fessor examines in detail the animal emals that live indifferently either on conomy in the class of amphibia, and land or in water, are amphibious; but fixes the characters that discriminate its the author by no means includes any species from other animals. A singulaof these : he treats solely of those ani- rity mentioned here is worthy of being mals that have an olleous skeleton, bones attended to. He says, that the poison fomenuhat hard, cold blood, that feen communicated by the bite of a vicold to the touch, that are not fishes, per, is fatal to all animals with warm that is, that are deftitute of a lateral blood, while those with cold blood opening serving for respiration. The are not at all affected by it: the viper Professor has already shewn, in his itself, the other European ferpents, excellent Tables of the Affinities of and the tortoises, fuffer hardly any Animals, that this last character very thing from this poison. The inge. clearly distinguishes the true amphibia nious Professor explains this phena from what are called the Cartilagi- menon in a very simple manner, and nous Fishes, or the Amphibia Nantia his opinion seems conformable to the of Linnæus, who had classed them laws of nature. We cannot doubt of with the rest for very plausible rea- the strength and influence of food on fons.

the animal creation ; since then, there

are . * Fortnights. The Hindoos have divided their lunar month into what they denominate the fookla-paksha, and the kreeftna-paksha, that is, the light fide and the dark side (of the moon;) the former commences with the new moon, and the latter with the full.

Obfervations on the Currents in the Atlantic Ocean. 389 are so many vegetables endowed with is of opinion, that they are not yet specific qualities, why may not these fufficiently numerous, and, besides, he qualities be communicated in a great- asserts that one species affords a result er or less degree to the animals that very different from that given by anofeed on them? But there are few in ther species, sometimes even from an the class of amphibia that live on individual of the same species, when plants, the greater part live on insects, examined at different seasons. worms, and even on other amphibi- The olfactory organ, in the class ous animals.

of amphibia, though a subject that deHave not all these animals them- serves much attention, has been little selves certain fpecific qualities, which investigated by moderns. The aumay be attributed to their food, or to thor, in this dissertation, relates a the acrimonious part of it more or multitude of facts little known on this less modified ? It is more than pro- head, or scattered here and there in bable that this acrimony is communi- books. On the whole, he appears to cated to the whole substance of the be a very intelligent naturalist, well animals of this class, and that on it acquainted with all the branches of . depend their medicinal virtues, their natural history, medicine, and the insensibility to venomous bites, and principal languages of Europe ; and even the subtilty of that poison which he has digested with method, clearis peculiar to the greatest part of them, ness, and precision, all the interesting after they have extracted the veno- particulars relative to this part of 200mous particles from the acrid sub- logy that are to be found in the ac.

Itances which they use as food. counts of Voyages and Travels pube • Chemists have made some experi- lished in every different language, ments on the component principles of where they have hitherto remained amphibious animals. Hermann re- inaccessible to the generality of the lo. lates these with learned remarks; he vers of nature.

Hydraulic and Nautical Observations on the Currents in the Atlantic Ocean,

&c. &c. By Governor Pownall, F. R. S. and F. A. S. 4to * T H E ingenious writer of this as matters which require, as they de

1 piece submits to the considera- ferve, farther and repeated obfervation of navigators, some observations tions, in a more regular and more scion the currents in the Atlantic Ocean, entific course of experiment. as applying to the use of navigation. Some of these observations arose

The studies which he pursued, and from his comparing notes, if we may the line of service in which he was so express it, with several of his Maemployed in the early part of his life, jesty's commissioned and warrant-offiled him and enabled him to make cers, in the frequent passages he had these observations.

occasion to make across the Atlantic, The facts and observations which in his Majesty's ships : other remarks, he states and describes, he throws out and the observations upon them, arose rather as matters of investigation than from the reports of American masters as things proved, although some have of trading and fishing vessels, with been determined by observation, and whom he conversed on the subject others are of common notoriety : but when he was Governor of Massachuit appears to him better to state them sett province, and whom he found to

understand, * Crit. Revo

understand the navigation of this 0. current which runs north-west, thro? cean better than the European mar- the old Bahama channel, meets at its ters seem to have done ; and who, in enbocheure, the current coming northconsequence of that knowledge, made eilt round the point from the gulf of shorter and better passages over it. Mexico ; and these, in one combined

The author reasons, that, in like current, set through the gulf of Flo. manner as the combined operation of rida north-easterly. From hence this attraction between the sun, moon, and current, in a bended and expanded earth, being uniform and permanent, flow, sets north-easterly along the coast produces an uniform and permanent of America, to about North latitude effect in the general tides of the O. 41 degrees and a half. The Govercean ; so the winds, when they are nor then remarks, that this course of uniform and permanent, produce, by the waters, produced by the constant protrusion, currents in the Ocean in blowing of the trade-winds across the like manner permanent and uniform. Atlantic Ocean, is analogous to carThe currents occasioned by the pro- rents produced by the periodical mon. trusion of the winds continue at all soons in the Southern and Indian feas: times fowing one way, either in the he then returns, and takes up the curdirection of the wind, or in a divergo rent of the gulf-stream, as it sets along ing lateral course, or in a reflexed the New-England coasts, where we recoiling current, as the waters piled before left it; and, from experienced up against any obstruction find the facts, states the following course and means of running off, and descending limits of it : namely, that the northfrom their forced elevation.

ern edge of the current lies in 381 The winds between the tropics ha- degrees of latitude in the meridian of ving a general courfe westwards, pro- the island Nantucket ; and, in the me trude the waters of the Atlantic Oc ridian of George's Bank, it is in las cean in the fame direction, and cause titude 39 degrees, where its course is a current running always nearly in the E. N. E. In the meridian of the fame direction. This general current, isle of Sable, its northern edge is in in passing through the chain of the 411 degrees ; and here itg course is Carribbee and Bahama islands, and a. E. S. E. and S. E. by E. Frons mongst the cayos of the same, is di- hence he traces the course of the curverted and drawn from its general rent across the Atlantic again, in a course in almost all directions. Where south-easterly direction, till it approach it is not interrupted or disturbed, it the coast of Africa, where it is des keeps its general course, as along the flected along the coast at some small Welt-Indian Sea, through the gulf of distance in a southerly direction, holdAlexico, to its bottom ; and in the ing that course till it arrive at, and channel between Hispaniola, Cuba, supply the place of those waters, car. and the cayos and ifiands of Bahama, ried by the constant trade-winds from to the gulf of Florida. The main the coast of Africa across the Atlancurrent, which runs directly west to tic, towards the west, as aforesaid ; the bottom of the gulf of Mexico, be- and thus producing a perpetual whiring there opposed by the continent, ling or circulating current, including piles up its waters to a considerable within its circuit a considerable breadth height. These aggregated waters run of space, forming a kind of eddy, or off laterally, and descend, as it were, perhaps returning or lee currents. . And down an inclined plane along the this state of the matter he observes, coats of Mexico, Louisiana, and Flo- compared by its causes, and in its efrida, and, rounding the fable point, it fects, is the actual fact. Tushes out of the gulf of Florida. The.. This current, thus revolving in an

Observations on the Currents in the Atlantic Ocean orbit round the Atlantic Ocean, in a fouth-western winds have prevailed for continual circulation, it is conform- any long time about the equinoxes, able to the laws of the hydraulics that and set in strong upon 'the northern there should be, in the space included coasts of Europe, and veer round welt within the inner edges of this orbit, and north, they pile up an aggregate an eddy, into which all floating sub- body of waters on the coalts of Norstances, such as wood and weeds, way. If this veering change of the which fall into the general current, wind happens about the time of the thail be finally absorbed. Now the full, or new moon, and about the time fact is, that weeds, called the Sara- of high-water on the coast of Norway, gofa weeds, as also the gulf-weeds, this aggregate body of waters, added have been observed at certain latitudes to the spring tides, pour down into and longitudes within the area of the the German Ocean such an inundation

orbit of this general current, and near of waters, as create these high raging E on what may be supposed the inner tides on the Dutch, Flemish, and Brie edge of it.

tish coasts, which so much furmount Altho' there are not in the north. all ordinary defences raised against ern parts of the Atlantic Ocean any them. If, under this coincidence of settled monsoon, or any trade-winds, the aforenamed circumstance, the wind as between the tropics ; yet, this au- should still more veer round with the thor obferves, to the northward of the fun, and come to east, just upon the space above described, a general east- setting of the tide into the German ern current takes place, running along Ocean, which has often happened, this the north boundary of this space, to inundation of these high raging tides

the east foutherly, across the Atlantic, will be blown over to the British coast, e towards the coasts of Europe, and fets and protruded through the channel to

continually through the Straits into the the west side of the Dogger's Bank, Mediterranean Sea; just as the cur- upon the English coasts, in such a

rent in the Indian Sea sets during the swollen and irresistible current, as hath e north-east monsoon into the gulf of at times, exceeding all bounds of de

Persia, and through the Straits of Ba. fence, done so much mischief to, and bel-Mandel into the Red Sea. Va- brought such ruin an, the maritime rious operations and combinations of parts of the country, where the springwinds, and various circumstances of rides occasioned by the moon do acbanks and elevated ground in this tually coincide, as above stated, with northern part of the Atlantic, may be the tide formed by protrusion of the afligned as causes of this effect. These winds ; they there come in as the are not yet fufficiently explored, even highest poslible flood, cæteris paribus :: not so much as to admit of a theore. when thcy do not, although combi. tic combination. The matter, how- ned, actually coincide in the fame ever, is fact, and of common noto- point of time, there is then always obriety, as is the fact that the passage served to be two tides, succeeding each from America to Europe is at least other at the distance of half an hour, one-third shorter than the passage from or more; that is to say, the moonEurope to America. It is so much tide, about its usual time, and the so, that it is a common expreslion a- great protruded wind-tide, half an mong the American navigators, that hour or more before or after. . the courfe is down hill all the way home, The author observes, that this exa' as they used to call England. Go- planation of the manner in which the vernor Pownall then remarks upon effect of protrusion of the winds, as the high tides, &c. in the German well as attraction, operates on the cur. Sea, and English channel: when the rents and tides of the German Sea, he


here incidentally makes, to suggest to of their course along the coasts of the landholders of these parts, the ne- Greenland, and the Elimaux shores, cellity there is of giving attention to if they should prove such as the rea, these circumstances, and of taking soning in this paper leads to, a much preparatory precaution to obviate and quicker passage yet may be found. guard off many of those evils they : By a particular and still more aehave repeatedly suffered, at least to curate examination of the northern guard them against being surprised, and southern edge of the Gulf-Strean, altho' perhaps adequate defence may of the variation of these circumstances, not be in their power.

as winds and seasons vary; and expe. He does not, however, mention rimental ascertaining what, where, and the foregoing as a precise or complete of what nature, the lee-currents on explanation of this dreadful phenome- the edges both inner and outer of the non, but obferves, that he is engaged Gulf-Stream are, great facilities and in a course of inquiry after every par- allistance must be derived to naviga ticular of the facts, their circumstance tion. The knowledge of this would and combination, as far as they may lead to the ascertaining the eddies, or be fuppofed to form the cause, and other partial currents in the great space create the effect of these high raging of ocean included within the great cir tides in the German Ocean ; that he culating current. The knowledge of may at least ascertain the prognostics the western edge of the current which with a sufficient degree of certainty sets fouth along the coasts of Africa, to the purposes of precaution and of all its variations, as also of the

Having stated, as above, not a lee-currents upon that edge, would be theory without foundation, or a mat- of essential use in navigating to (and ter as proved, but a hypothetical theo- perhaps from) the West Indies. A rem for investigation by experiment, practical knowledge of the variable the writer, instead of drawing con- currents, and how they vary under 0. clusions, closes his observations, after peration of various causes, in the space pointing out fome uses of them, by aforenamed, as running across the At proposing some queries as matters well lantic, might be of great benefit in forworthy of trial and inquiry. . warding a quick passage from Ameri..Skilful navigators, who have ac- ca, perhaps in shortening the passage quired a knowledge of the extent to thither in Winter. Various other uses which the northern edge of the Gulf of this inquiry might be pointed out, Stream 'reaches on the New England but to have marked that this hypothecoast, have learnt in their voyages to tic theorem is not without its use, is New-England, New York, or Penn- fufficient.' fylvania, to pass the banks of New A neat sheet map accompanies the foundland in about 440 or 450 N. book, upon which the current is marklatitude, to fail thence, in a course ed by a dark shade, very exact as to between the northern edge of the Gulf the northern latitudes of the edges of Stream, as above described, and the it; and the shade is lighter and lightThoals and banks of Sable Illand, er as the stream expands, and grows George's Bank, and Nantucket, by weaker so as almost to vanish as it apo which they make better and quicker proaches the African coast. The un passages from England to America. der or southern edge is engraven alfo, 1. By an examination of the cur- but with an indecisive line, as being rents in the higher latitudes of the known with a less degree of certainty. Dorthern parts of the Atlantic, and

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