388 Remarks on the Qualities and Properties of Amphibious Animals. diforder, and ran away. The master ordinary good or bad action in the fpace of three years, three months, three fortnights *, or three days. Wherefore I repeat, Harmony between the food and the feeder, c. Amphibiorum Virtutis Medicata Defenfio. HIS is the firft part of a work ΤΗ that will be very acceptable to the learned, efpecially to Naturalifts: the prefent fafciculus contains only fome general remarks on the qualities and properties of amphibious animals; the fubfequent parts will comprehend a particular account of the genera and fpecies in the clafs of amphibia; and it is there in particular that we fhall find ourselves indebted for a great number of new experiments and observations, to Profeffor Hermann, one of the first naturalifts in Europe. In the vulgar acceptation of the word amphibia, the otter, the beaver, the feal, and, in general, all the animals that live indifferently either on land or in water, are amphibious; but the author by no means includes any of these he treats folely of thofe animals that have an offecus fkeleton, bones fomewhat hard, cold blood, that feem cold to the touch, that are not fishes, that is, that are deftitute of a lateral opening ferving for refpiration. The Profeffor has already fhewn, in his excellent Tables of the Affinities of Animals, that this last character very clearly distinguishes the true amphibia from what are called the Cartilaginous Fishes, or the Amphibia Nantia of Linnæus, who had claffed them with the rest for very plaufible reafons. By John Hermann, Profeffor of Thus, therefore, the amphibia of Hermann comprehend but a fmall number of genera, to wit, the tortoise, the toad, the frog, the lizard, the falamander, the flying lizard, and the whole family of ferpents. But if the genera here are few, the fpecies are exceedingly numerous; the greater part of them too are little known, and it is very difficult to distinguish them from one another. As M. Hermann is occupied in illuftrating this part of natural history, we are impa tient for the continuation of his work. In this firft fection, which is the fubject of our review, the learned Profeffor examines in detail the animal economy in the class of amphibia, and fixes the characters that discriminate its fpecies from other animals. A fingularity mentioned here is worthy of being attended to. He fays, that the poifon communicated by the bite of a viper, is fatal to all animals with warm blood, while thofe with cold blood are not at all affected by it: the viper itself, the other European ferpents, and the tortoifes, fuffer hardly any thing from this poifon. The ingenious Profeffor explains this pheno menon in a very fimple manner, and his opinion feems conformable to the laws of nature. We cannot doubt of the ftrength and influence of food on the animal creation: fince 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 fide (of the moon;) the former commences with the new moon, and the lat ter with the full. Obfervations on the Currents in the Atlantic Ocean. are fo many vegetables endowed with fpecific qualities, why may not thefe qualities be communicated in a greater or lefs degree to the animals that feed on them? But there are few in the clafs of amphibia that live on plants, the greater part live on infects, worms, and even on other amphibious animals. 389 is of opinion, that they are not yet fufficiently numerous, and, befides, he afferts that one fpecies affords a result very different from that given by another fpecies, fometimes even from an individual of the fame fpecies, when examined at different feafons. The olfactory organ, in the clafs of amphibia, though a fubject that deferves much attention, has been little inveftigated by moderns. The author, in this differtation, relates a multitude of facts little known on this head, or fcattered here and there in books. On the whole, he appears to be a very intelligent naturalift, well Have not all these animals themfelves certain specific qualities, which may be attributed to their food, or to the acrimonious part of it more or lefs modified? It is more than probable that this acrimony is communicated to the whole fubftance of the animals of this clafs, and that on it acquainted with all the branches of depend their medicinal virtues, their infenfibility to venomous bites, and even the fubtilty of that poifon which is peculiar to the greatest part of them, after they have extracted the venomous particles from the acrid fubftances which they ufe as food. Chemifts have made fome experiments on the component principles of amphibious animals. Hermann relates thefe with learned remarks; he of zoo natural hiftory, medicine, and the Hydraulic and Nautical Obfervations on the Currents in the Atlantic Ocean, &c. &c. By Governor Pownall, F. R. S. and F. A. S. 4to *. T HE ingenious writer of this piece fubmits to the confideration of navigators, fome obfervations on the currents in the Atlantic Ocean, as applying to the use of navigation. The ftudies which he purfued, and the line of fervice in which he was employed in the early part of his life, led him and enabled him to make thefe obfervations. The facts and obfervations which he ftates and describes, he throws out rather as matters of inveftigation than as things proved, although fome have been determined by obfervation, and others are of common notoriety: but it appears to him better to ftate them as matters which require, as they deferve, farther and repeated obfervations, in a more regular and more scientific courfe of experiment. Some of thefe obfervations arofe from his comparing notes, if we may fo exprefs it, with feveral of his Majefty's commiffioned and warrant-officers, in the frequent paffages he had occafion to make across the Atlantic, in his Majefty's fhips: other remarks, and the obfervations upon them, arose from the reports of American masters of trading and fishing veffels, with whom he converfed on the subject when he was Governor of Maffachufett province, and whom he found to understand, * Grit. Rev, understand the navigation of this Ocean better than the European mafters feem to have done; and who, in confequence of that knowledge, made shorter and better paffages over it. The author reafons, that, in like manner as the combined operation of attraction between the fun, moon, and earth, being uniform and permanent, produces an uniform and permanent effect in the general tides of the Ocean; fo the winds, when they are uniform and permanent, produce, by protrufion, currents in the Ocean in like manner permanent and uniform. The currents occafioned by the protrufion of the winds continue at all times flowing one way, either in the direction of the wind, or in a diverging lateral course, or in a reflexed recoiling current, as the waters piled up against any obftruction find the means of running off, and defcending from their forced elevation. The winds between the tropics having a general courfe weftwards, protrude the waters of the Atlantic Ocean in the fame direction, and cause a current running always nearly in the fame direction. This general current, in paffing through the chain of the Carribbee and Bahama islands, and amongst the cayos of the fame, is diverted and drawn from its general course in almost all directions. Where it is not interrupted or difturbed, it keeps its general courfe, as along the Weft-Indian Sea, through the gulf of Mexico, to its bottom; and in the channel between Hifpaniola, Cuba, and the cayos and islands of Bahama, to the gulf of Florida. The main current, which runs directly weft to the bottom of the gulf of Mexico, being there oppofed by the continent, piles up its waters to a confiderable height. Thefe aggregated waters run off laterally, and defcend, as it were, down an inclined plane along the coafts of Mexico, Louisiana, and Florida, and, rounding the fable point, it rushes out of the gulf of Florida. The current which runs north-west, thro the old Bahama channel, meets at its embocheure, the current coming northet round the point from the gulf of Mexico; and these, in one combined current, fet through the gulf of Florida north-eafterly. From hence this current, in a bended and expanded flow, fets north-easterly along the coaft of America, to about North latitude 41 degrees and a half. The Governor then remarks, that this course of the waters, produced by the conftant blowing of the trade-winds across the Atlantic Ocean, is analogous to currents produced by the periodical monfoons in the Southern and Indian feas: he then returns, and takes up the current of the gulf-ftream, as it fets along the New-England coafts, where we before left it; and, from experienced facts, ftates the following courfe and limits of it: namely, that the northern edge of the current lies in 38 degrees of latitude in the meridian of the island Nantucket; and, in the meridian of George's Bank, it is in latitude 39 degrees, where its course is E. N. E. In the meridian of the ifle of Sable, its northern edge is in 41 degrees; and here its course is E. S. E. and S. E. by E. From hence he traces the courfe of the current acrofs the Atlantic again, in a fouth-cafterly direction, till it approach the coast of Africa, where it is deflected along the coaft at fome small diftance in a foutherly direction, holding that courfe till it arrive at, and fupply the place of thofe waters, carried by the conftant trade-winds from the coast of Africa across the Atlan tic, towards the weft, as aforefaid; and thus producing a perpetual whirling or circulating current, including within its circuit a confiderable breadth of space, forming a kind of eddy, or perhaps returning or lee currents. And this ftate of the matter he obferves, compared by its caufes, and in its effects, is the actual fact. This current, thus revolving in an Obfervations on the Currents in the Atlantic Ocean. 391 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 fet in ftrong upon the northern there fhould be, in the fpace included coafts of Europe, and veer round west within the inner edges of this orbit, and north, they pile up an aggregate an eddy, into which all floating fub- body of waters on the coafts of Norftances, fuch as wood and weeds, way. If this veering change of the which fall into the general current, wind happens about the time of the hall be finally abforbed. 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 alfo the gulf-weeds, this aggregate body of waters, added have been obferved at certain latitudes to the fpring tides, pour down into and longitudes within the area of the the German Ocean fuch an inundation orbit of this general current, and near of waters, as create these high raging on what may be fuppofed the inner tides on the Dutch, Flemish, and Briedge of it. tish coafts, which fo much furmount all ordinary defences raised against them. If, under this coincidence of the aforenamed circumftance, the wind fhould still more veer round with the fun, and come to eaft, just upon the fetting of the tide into the German Ocean, which has often happened, this inundation of these high raging tides will be blown over to the British coast, and protruded through the channel to the weft fide of the Dogger's Bank, upon the English coafts, in fuch a fwollen and irresistible current, as hath at times, exceeding all bounds of defence, done fo much mischief to, and brought fuch ruin an, the maritime parts of the country, where the springtides occafioned by the moon do ac tually coincide, as above ftated, with the tide formed by protrusion of the winds; they there come in as the highest poffible flood, cæteris paribus :: when they do not, although combined, actually coincide in the fame point of time, there is then always obferved to be two tides, fucceeding each other at the distance of half an hour, or more; that is to fay, the moontide, about its ufual time, and the great protruded wind-tide, half an hour or more before or after. Altho' there are not in the northern parts of the Atlantic Ocean any fettled monfoon, or any trade-winds, ás between the tropics; yet, this author obferves, to the northward of the space above described, a general eastern current takes place, running along the north boundary of this fpace, to the east foutherly, across the Atlantic, towards the coafts of Europe, and fets continually through the Straits into the Mediterranean Sea; juft as the current in the Indian Sea fets during the north-east monfoon into the gulf of Perfia, and through the Straits of Babel-Mandel into the Red Sea. Various operations and combinations of winds, and various circumftances of banks and elevated ground in this northern part of the Atlantic, may be afligned as caufes of this effect. Thefe are not yet fufficiently explored, even not so much as to admit of a theoretic combination. The matter, however, is fact, and of common notoriety, as is the fact that the paffage from America to Europe is at least one-third shorter than the paffage from Europe to America. It is fo much fo, that it is a common expreffion among the American navigators, that the courfe is down hill all the way home, as they used to call England. Governor Pownall then remarks upon the high tides, &c. in the German fea, and English channel: when the The author obferves, that this explanation of the manner in which the effect of protrufion of the winds, as well as attraction, operates on the currents and tides of the German Sea, he here here incidentally makes, to fuggeft to the landholders of these parts, the neceffity there is of giving attention to thefe circumftances, and of taking preparatory precaution to obviate and guard off many of thofe evils they have repeatedly fuffered, at least to guard them against being furprised, altho' perhaps adequate defence may not be in their power. of their courfe along the coafts of Greenland, and the Eskimaux fhores, if they should prove fuch as the reafoning in this paper leads to, a much quicker paffage yet may be found. By a particular and ftill more accurate examination of the northern and fouthern edge of the Gulf-Stream, of the variation of these circumftances, as winds and seasons vary; and expeHe does not, however, mention rimental afcertaining what, where, and the foregoing as a precife 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 courfe of inquiry after every par- affiftance must be derived to naviga ticular of the facts, their circumftance tion. The knowledge of this would and combination, as far as they may lead to the afcertaining the eddies, or be fuppofed to form the caufe, and other partial currents in the great space create the effect of these high raging of ocean included within the great cirtides in the German Ocean; that he culating current. The knowledge of may at least afcertain the prognostics the western edge of the current which with a fufficient degree of certainty fets fouth along the coafts of Africa, to the purposes of precaution. and of all its variations, as alfo of the lee-currents upon that edge, would be of effential ufe in navigating to (and perhaps from) the Weft Indies. A practical knowledge of the variable currents, and how they vary under operation of various caufes, in the space aforenamed, as running across the Atlantic, might be of great benefit in forwarding a quick paffage from America, perhaps in fhortening the paffage thither in Winter. Various other ufes of this inquiry might be pointed out, but to have marked that this hypothetic theorem is not without its use, is fufficient." Having ftated, as above, not a theory without foundation, or a matter as proved, but a hypothetical theorem for investigation by experiment, the writer, instead of drawing conclufions, clofes his obfervations, after pointing out fome uses of them, by propofing fome queries as matters well worthy of trial and inquiry. Skilful navigators, who have acquired a knowledge of the extent to which the northern edge of the Gulf Stream 'reaches on the New-England coaft, have learnt in their voyages to New-England, New York, or Pennfylvania, to pafs the banks of Newfoundland in about 440 or 45° N. latitude, to fail thence, in a courfe between the northern edge of the Gulf Stream, as above defcribed, and the fhoals and banks of Sable Ifland, George's Bank, and Nantucket, by which they make better and quicker paffages from England to America. By an examination of the currents in the higher latitudes of the northern parts of the Atlantic, and A neat fheet map accompanies the book, upon which the current is marked by a dark fhade, very exact as to the northern latitudes of the edges of it; and the fhade is lighter and lighter as the ftream expands, and grows weaker fo as almost to vanish as it approaches the African coaft. The under or fouthern edge is engraven alfo, but with an indecifive line, as being known with a lefs degree of certainty. An |