Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/549

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George Graham, and executed with furprifing exaclnefs. With this inftrumcnt the ftar y, in the conftellation Draco, was frequently obferved by Meffrs. Molyneux, Bradley, and Graham, in the years 1725, 1726; and the obfervations were afterwards repeated by Mr. Bradley, with an instru- ment contrived by the fame ingenious perfon, Mr. Graham, and fo exa£t, that it might be depended on to half a fecond. The refult of thefe obfervations was, that the ftar did not always appear in the fame place, but that its distance from the zenith varied, and that the difference of the apparent places of Themis, the third fatelKte of Jupiter, amounted to 21 or 22 feconds. Similar obfervations were made on other fears, and a like apparent motion was found in them, proportional to the latitude of the ftar. This motion was by no means fuch as was to have been expected, as the effect: of a parallax ; and it was fome time before any way could be found of accounting for this new phenomenon. At length Mr. Bradley refolved all its variety, in a fatisfactory manner, by the motion of light and the motion of the earth compounded together. See Light.

Star, ftarrum, in our old writers. All the deeds, obligations, &c. of the Jews, were called fears, and writ for the moft part in Hebrew alone, or in Hebrew and Latin ; one of which yet remains in the Treafury of the Exchequer, written in Hebrew without points, the fubftance whereof is expreffed in Latin jufi: under it, like an Englifh condition under a Latin obligation : this bears date in the reign of King John ; and many fears ', as well of grant and releafe, as obligatory, and by way of mortgage, are pleaded and recited at large in the Plea Rolls. Pafch. oEdw. I. Blount. The word ftar is a contraction from the Hebrew febetar, a deed or contract.

Star of the earthy in botany, the name of a plant famous for its virtues in curing the bite of a mad-dog: but unhappily there has been a very great mifunderftanding among authors about the plant properly fignified by this name ; fome calling by it the coronopus, or buckthorn-plantain, an herb common every where, and others a fpecies of lychnis, or catch-fly, which is a very fcarce plant. The original account of its nature and virtues feems to be this : King James fent to the

' Royal Society a dried fpecimen of a plant, which had been fent to him as the plant with which his dogs had been cured when bitten by a mad-dog, and the name, by which this was called, was ftar of the earth.

The plant was fo ill dried, that it was not eafily diiKnguifh- ed, but at length Mr. Ray found it to be the fefamoldes fa- lamantkum magnum. It does not feem, however, clear, that this was the plant vulgarly known by that name, but rather that it was gathered by fome ignorant perfon ; neither the name ftar of the earth at all agreeing with it, nor any ac- count having been given before of its having fuch virtues. Dr. Grey, in his Compleat Farrier, greatly recommends the fear of the earth in the cure of this bite, and the plant he means is plainly the coronopus, or buckihorn-plantane : and, upon the whole, it feems that this laft mentioned is the plant properly called by this name, as its virtues have always been celebrated even in this cafe, and its leaves always are difpofed on the earth in the form of the rays of a ftar. It is to be added to this, that the Countefs of Suffolk's powder, fo famous in many places for this terrible difeafe, and by which feveral perfons have been known to be cured, is principally compofed of this plant- Philof. Tranf. N° 450. p. 455.

Star-j^. There are many fpecies of the ftar-fijh, and thofe extremely different one from another : they have different numbers of rays, but the moft common kind has five. Their upper furface, or that to which the legs are not fattened, is covered with a firm and hard fkin, which is full of little eminences of a harder matter, approaching to the nature of thatof the fhellsofthe echini marini, and the like. This fkin is of different colours in the different fpecies ; moft ufually it is red, fometimes it is green, in fome blue, and in others yel- low, and of all the degrees of thefe colours, or the mixtures that may be produced from. them. This colour does not extend to the under furface, that is covered all over with legs and with points, like the eminences of the upper fide, only longer ; thefe are all either whitifh, or yellowifh. In the center of the fijb there may be feen a mouth or fucker, by means of which the creature draws its nourifhment from the mell-nfh, on which it feeds. There are five teeth placed round this fucker, or perhaps they may be more properly called five bony forceps; by means of which it feizes and holds faff the creature, while the fucker does its office in draining out the juices; and probably it is by means' of thefe that they open the bivalve fhells 3 when they feed on the fifh in them.

Every ray of the fear-fiflj is furnifhed with fo very large a number of legs, that they cover the whole furface : they are difpofed in four ranges, each of which contains about 74 ; f that the whole ray contains 304, and confequently the 'fifij has, upon all five of its rays, no lefs than 1520 le«s. With all this numerous train of legs, however, the animal moves but very {lowly ; and indeed they are fo foft and feeble, that they fcarce deferve the name of legs, and, more properly fpeaking, they are only a fort of horns, like thofe of our

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f'^Ztf 8 ' ^^ fc 7 ethfean!maI *> walk with, ana 1 are therefore called legs. It is not only in their foftnefi that they refemble the horns of (hails, hut their figure s a fd perfectly hke them,, fo as that the eomparifon give, a fuffi-

SL r T n ° f ?•& They m C S* of bd "S con- tracted or fhortened alfd, in the fame manner with the

horns of fnails, and it is only in the time of the creature's moving that they are feen of their full length ; at other tunes no part of them is feen but the extremity of each, which is formed like a fort of button, being fomewhat larger than the reft of the horn. If one of the rays of this fijb Be turned the lower part upwards, and attentively viewed; the mechanifm by which it extends its legs will be eafily underflow!. If the ray be cut tranfverfely in two, it is found compofed of two bodies, divided from one another by a cartilaginous hard fubftance. This body feems compofed of a vaft number of vertebra:, and along it there run a great number of fphcrical, or oblong tubercles, very bright and tranfparent. There are four ranges of thefe, on each fide two ; they are formed of a fine thin tranfparent mem- brane, filled with a perfcflly clear and pellucid fluid, like water. It is not difficult to conceive, that thefe little blad- ders ferve to the lengthening and contracting of the legs of the animal ; it is foon perceived that they are of the fame number with the legs, and are ranged in 'the fame order, fo that each bladder correfponds to one leg : but the whole is perfectly explained, when on preffing one of thefe bladders the liquor is feen to flow out of it into the leg which it belongs to, and that the leg is extended and lengthened by this means ; and that when this preffure is taken off, the fluid runs back again of itfelf from the leg to the bladder, and that on this the leg gradually ftionens again : there is, therefore, nothing more necefliry for the lengthening and contraaing of the legs, than that the animal f'hould have a power of preffing thefe bladders ; that would always perform the firft motion, and the mere ccafing to prefs. them would perform the other.

When the under part of the rays is viewed, and the creature in motion, it is feen that the legs are elongated, and again contracted, merely by the ingrefs and egrefs of a fluid ; and that the creature does not ufe all the legs of the fame ray to walk with, but fometimes one part of them, and fometimes another, and this with great irregularity. They feize on any part of the rock, in the creature's moving, in an acute angle, and in coiifequence, when they fet themfelves ftrait upright again the body of the fifh, muft be fo far pulled for- ward, as is the fpace of that angle from the perpendicular; They march with equal eafe when thus inverted, and when in their natural pofition, and as well on fand as ftones, and if in the dry, or if covered with water ; but in all cafes they move very llowly.

If * ftar-fijh is taken up when full of water, it throws it out at different parts of its body by a vaft number of little; and almoft imperceptible apertures, in fo many fmall ftreams or threads ; and when it has difcharged thus all that it will naturally, it may be made to throw out more by preffing or fqueezing the rays, and by this means the pipe, by which it is thrown out, may be forced out of the body, and is then feen to be white, and of a triangular, not round figure. Thefe are difpofed in great numbers over the rays. Mem. Acad. Par. 1710.

The amazing property of reproducing the effential parts, when loft, is not confined to the polype, and fome few others of the infect world, but is extended to the ftar-fijh, and to the urtica: marina? of various kinds, and probably to many others, in which we at prefent have no expectation of finding it. Mr. Reaumur, on the difcovery of this prc- perty in the polype, obferved thefe other animals, as they lay on the fhores of Poictou, and other places, and often found that fpecies of ftar-fijh, which is very commonly known, and which has naturally five rays or arms; with only three or four, one or two being wanting; and on tak- ing up and examining thefe mutilaled ones, nature was al- ways found reproducing the limb that was wanting ; and on cutting and breaking other fiar-fijli into feveral parts, it was but a very little while before the broken parts cicatrifed, and every part remained alive ; and by the appearances of things there remained no doubt, but that thefe living pieces will all, in time, reproduce their wanting parts. Mr. Reaumur could not flay long enough on the fpot to fee this, but Mr. de Villars, on the coaft of Rochelle, faw the whole procefs very frequently in the ufticae marina?, which he cut to pieces on purpofe for the experiment, and which always reproduced the parts he had cut off; and the common fifhermen of the coafts, where Mr. Reaumur was in company with Mr. Juffieu, feeing them making their experiments on foeftar-fijhes, appeared to be well acquaint- ed with their nature, and told them that they mi^ht cut and tear them as much as they pleafcd, but they would not be able to kill them: fo familiarly was this piece of natural hiftory known among thefe people, though unknown to thofe who had employed their lives in the fearches after fuch things.

Mr.