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equal to 1" daily. Whence, if the clock be so length of the common half second pendulum. adjusted as to keep time when the thermometer Let

O be the focus of the parabola MI E C, and is at 55°, it will lose 10' daily when the thermo- M C the latus rectum; and make A E=MO meter is at 65°, and gain as much when it is at = $MC= the length of a common half se45°. Hence the daily variation of the rate of the cond pendulum. At the point A of the verge clock from summer to winter will be very consi- let a thin plate A B be fixed at one end, and at derable. It is true indeed that most pendulums the other end B let it be fastened to a bar or arm have a nut or regulator at the lower end, by B D. perpendicular to DH, and to which it is which the bob may be raised or lowered a de- fixed at the point D. The figure of the plate terminate quantity: and therefore, while the A B is that of the evolute of the given parabola height of the thermometer is the same, the rate of MEC. The equation of this evolute, being also the clock will be uniform. But since the state of that of the semicubical parabola, is pr = yo.

27 the weather is ever variable, and as it is impossi

16 ble to be raising or lowering the bob of the pen

27 dulum at every change of the thermometer, there- - Let 78 P=P; then Pro=y', and in the focus fore the correction formerly mentioned is to be applied. This correction, however, is in some P= 2y. In this case 2 r2 = y'= {P?: hence measure liable to a small degree of uncertainty; r = | P2, and r = PNT=

27 and, in order to avoid it altogether, several con

PV = the

16 trivances have been proposed, by constructing a distance of the focus from the vertex A.-By aspendulum of different materials, and so disposing suming the value of x, the ordinates of the curve them that their effects may be in opposite direc- may be found; and hence it may be easily tions, and thereby counterbalance each other; and drawn. The string of the pendulum must be of thus the pendulum will continue of the same length. such a length that, when one end is fixed at B, it

Penrulum, ANGULAR, is formed of two pieces may lie over the plate A B, and then hang peror legs like a sector, and is suspended by the an- pendicular from it, so that the centre of the bob gular point. This pendulum was invented with may be at E when at rest. Now, the verge K H a view to diminish the length of the common being put in motion, the ball of the pendulum pendulum, but at the same time to preserve or will begin to gyrate, and thereby contrive a ceneven increase the time of vibration. In this pen- trifugal force which will carry it out from the dulum, the time of vibration depends on the axis to some point F, where it will circulate selength of the legs, and on the angle contained conds or half seconds, according as the line A E between them conjointly, the duration of the is 9.8 inches, or two inches and a quarter, time of vibration increasing with the angle. and A B answerable to it. One advantage posHence a pendulum of this construction may be sessed by a clock having a pendulum of this conmade to oscillate in any given time. At the structior. is, that the second hand moves in a lower extremity of each leg of the pendulum is a regular and uniform manner, without being subball or bob as usual. It may be easily shown, ject to those jerks or starts as in common clocks; that, in this kind of a pendulum, the squares of and the pendulum is entirely silent. the times of vibration are as the secants of half PENDULUM, Fir. The expansion or contracthe angle contained by the legs: hence, if a pen- tion of straight-grained fir wood lengthwise, by dulum of this construction vibrates half seconds change of temperature, is so small that it is when its legs are close, it will vibrate whole se- fonnd to make very good pendulum rods. The conds when the legs are opened, so as to contain wood called sapadillo is said to be still better. an angle equal to 151° 2° 30".

There is good reason to believe that the previPENDULUM, Conical, or circular, is so call- ous baking, varnishing, gilding, or soaking of ed from the figure described by the string or ball these woods in any melted matter, only tends to of the pendulum. This pendulum was invented impair the property that renders them valuable. by Mr. Huygens, and also claimed by Dr. They should be simply rubbed on the outside Hook. To understand its principles it will be with wax and a cloth. In pendulums of this necessary to premise the following lemma, viz. construction the error is greatly diminished, but the times of all the circular revolutions of a heavy not taken away. globular body, revolving within an inverted hol- PenduLUM, GRIDIRON, or Harrison's, is an low paraboloid, will be equal, whatever be the ingenious contrivance for the purpose aboveradii of the circles described by that body. To mentioned. Instead of one rod, this pendulum construct the pendulum, therefore, so that its ball is composed of any convenient odd number of may always describe its revolutions in a parabo- rods, as five, seven, or nine; being so connected loid surface, it will be necessary that the rod of that the effect of one set of them counteracts that the pendulum be flexible, and that it be suspended of the other set; and therefore, if they are proin such a manner as to form the evolute of the perly adjusted to each other, the centres of susgiven parabola. Hence, let K H (fig. 9) be an pension and oscillation will always be equidistant. axis perpendicular to the horizon, having a pi- Fig. 7 represents a gridiron pendulum composed pion at à moved by the last wheel in the train of nine rods, steel and brass alternately. The of the clock; and a hardened steel point at H two outer rods, A B,C D, which are of steel, are moving in an agate pivot, to render the motion fastened to the cross pieces A C, B D, by means as free as possible. Now, let it be required that of pins. The next two rods, E F, GH, are of the pendulum shall perform each revolution in a brass, and are fastened to the lower bar B D, and second ; then the paraboloid surface it moves in to the second upper bar E G. The two followmust be such whose latus rectum is double the ing rods are of steel, and are fastened to the cross.

bars E G and I k. The two rods adjacent to the have the following description in the Transactions central rod, being of brass, are fastened to the of the Royal Irish Academy, 1788:-* A and cross pieces I K and L M; and the central rod, B, fig. 8, are two rods of steel forged out of ine 10 which the ball of the pendulum is attached, is same bar, at the same time, of the saine temper, suspended from the cross piece L V, and passes and in every respect similar. On the top of B freely through a perforation in each of the cross is formed å gibbet C; this rod is firmly supbars" IK, BD. From this disposition of the ported by a steel bracket D, fixed on a large rods, it is evident that, by the expansion of the piece of marble E, firmly set into the wall F, extreme rods, the cross piece BD, and the two and having liberty to move freely upwards berods attached to it, will descend: but, since these tween cross staples of brass, 1, 2, 3, 4, which rods are expanded by the same heat, the cross touch only in a point in front and rear (the stapiece E G will consequently be raised, and there- ples having been carefully formed for that puriore also the two next rods; but, because these pose); to the other rod is firmly fixed by its ods are also expanded, the cross bar I K will centre the lens G, of twenty-four pounds weight, descend; and, by the expansion of the two next although it should in striciness be a little below rus, the piece L M will be raised a quantity suf- it. This pendulum is suspended by a short steel ficient to counteract the expansion of the central spring on the gibbet at C; all which is entirely rod. Whence it is obvious that the effect of the independent of the clock. To the back of the steel rods is to increase the length of the pendu- clock-plate I are firmly screwed two cheeks luni in hot weather, and to diminish it in cold nearly cycloidal at K, exactly in a line with the weather, and that the brass rods have a contrary centre of the verge L. The maintaining power effect upon the pendulum. The effect of the brass is applied by a cylindrical steel stud, in the usual rods must, however, be equivalent, not only to way of regulators, at M. Now it is very evithat of the steel rols, but also to the part above dent that any expansion or contraction that takes the frame and spring, which connects it with the place in either of these exactly similar rods is clock, and to that part between the lower part of instantly counteracted by the other; whereas in the frame and the centre of the ball.

all compensation pendulums composed of difPENDULUM, MERCURIAL, was invented by ferent materials, however just calculation may the celebrated Mr. George Graham, and is con- seem to be, that can never be the case, as not sidered as the compensating pendulum. In this only different metals, but also different bars of the rod of the pendulum is a hollow tube, in the same metal that are not manufac!ured at the which a sufficient quantity of mercury is put. same tiine, and exactly in the same manner, are Mr. Graham first used a glass tube, and the clock found by a good pyrometer to differ materially to which it was applied was placed in the most in their degrees of expansion and contraction, a exposed part of the house. It was kept constant- very small change affecting one and not the ly going, without having the hands or pendulum other.' Theory has pointed out several other altered, from the 9th of June 1722 to the 14th of pendulums, known by the names of elliptic, hoOctober 1725, and its rate was determined by rizontal, rotulary, &c., pendulums. We can only transits of fixed stars. Another clock made with select two or three of the more modern inrenextraordinary care, having a pendulum about tions of this kind. sixty pounds weight, and not vibrating above 1° Elliott's compensating pendulum. — The adjust30' from the perpendicular, was placed beside ment of the rods for the temperature in the Gridthe former, the more readily to compare them iron pendulum of IIarrison being found in with each other, and that they might both be convenient, and accompanied sometimes by a equally exposed. The result of all the observa- considerable change in the rate : in the pendu tions was this, that the irregularity of the clock lum of Elliott two levers are adopted instead o. with the quicksilver pendulum exceeded not, one, and they are applied at the bob instead of when greatest, a sixth part of that of the other at the superior end of the verge. clock with the common pendulum, but for the Fig. 1, plate II., PENDULUMS, represents this greatest part of the year not above an eighth or pendulum; ab is a bar of brass made quite fast ninth part; and even this quantity would have at the upper end by pins, and held contiguous at been lessened, had the column of mercury been several equal distances, by the screws, 1, 2, &c., a little shorter: for it differed a little the contrary to the rod of the pendulum, which is a bar of way from the other clock, going faster with heat iron ; and, so far as the brass bar reaches, is filed and slower with cold. To confirm this experi- of the same size and shape, though it does nol ment more, about the beginning of July 1723 appear so in the figure, but, a little below the Mr. Graham took off the heavy pendulum from end of the brass, the iron is left broader, as at the other clock, and made another with mercury, dd. for the conveniency of fixing the work to it, but with this difference, that instead of a glass and is made of a sufficient length to pass quite tube he used a brass one, and varnished the in- through the ball of the pendulum 10 c. The side to secure it from being injured by the mer- holes 1, 2, &c., in the brass, through which the cury. This pendulum he used afterwards, and screws pass into the iron rod of the pendulum, found it about the same degree of exactness as are filed of a sufficient length to suffer the brass the other.

to contract and dilate freely hy heat and cold M. Thiout's Pendulum.- Another excellent under the heads of the screws : eeee represent contrivance for the same purpose is described the ball of the pendulum ; f;f; two strong pieces by M. Thiont, a French author on clock-making. of steel, or levers, whose inner centres, or pivots, Of this pendulum, somewhat improved by Mr. turn in two holes drilled in the broad part of the Crosthwaite, watch and clock maker, Dublin, we pendulum rod, and their outer ones in a strong bridge, or cock, screwed upon the same part of make it useful as such, it carries a graduated the rod, but omitted in the figure, to show the scale. The tube in question is about the size of mechanism : g, g, are two screws entering at the a barometer tube, and the bulb large enough to edges, and reaching into the cavity near the cen- contain forty-five ounces of pure mercury by the tre of the ball. The ends of the screws next the aid of one-half the tube. Fig. 2 of plate II. centre are turned into the form seen in the figure, exhibits Mr. Troughton's arrangement. A B is which, pressing with the weight of the ball the mercurial rod filled with mercury to the midagainst the longer arms of the levers, cause the dle point of the rod; C D the bulb guarded by short ends to press against the brass bar at b. the surrounding lenticular bob of brass and lead Let us now suppose that the rod of the pendu- made in the usual way, except that it is hollow lum, and the brass annexed to it, grow longer in the centre: the metallic parts of the pendulum by heat, and that the brass lengthens more than weigh about nine pounds exclusively of the merthe iron of the same length; then the brass, by cury; the rim that surrounds the bulb, and by the excess of its dilation, will press the short which the weight of the lenticular bob is supends of the levers downwards at b, and at the ported, projects into two notches cut in the insame time necessarily lift up the ball, which ierior edges of the metallic leus, at each side of rests on the long ends of the same lever, at ff, the cavity, and the nice fitting of the bulb to its to any proportion necessary for due compensa- rim renders the glass capable of bearing the tions. The calculated proportion of the short weight of metal supported by it. The compenarms of the levers musi be to the long ones as sation of this pendulum is effected entirely by the excess in the expansion of brass is to that of the ascent and descent, alternately, of the merthe whole length of iron; and, if this calculation cury up and down the glass tube as the heat be found on trial not perfectly accurate, the side varies; and as the expansion of glass varies much screwsg, g, will produce the exact compensation less than that of any of the metals, the small at a few adjustments. At ik, the inferior end of column of mercury contained in the tube is the iron verge, a strong double spring is fixed to found sufficient to answer its purpose completely bear the major part of the ball's weight, by its after a trial of more than twenty years. pressure upwards against two points of the ball, Ward's compensation pendulum.-- This is an inequidistant from the vertical line. This is the vention of Mr. Henry Ward, of Blandford in Dordescription of the first pendulum made in this setshire, who, in March 1806, communicated it way; and the only alteration that the inventor to the Society of Arts, accompanied by a model, made afterwards was placing the side screws in which gained him the silver medal of the society. the body of the ball. Cumming proposes, in his It consists of three bars, two of iron and one of Elements of Clock and Watch-work, that the zine, arranged in a manner very similar to Debrass bar should elongate between two iron bars, parcieux’s improvement of Regnauld's old French in order to keep it straight, and to prevent thé pendulum, but without the adjustment lever. jerks to which he conceives the foregoing con- The instrument appears in fig. 3, plate II., where struction liable: he proposes also to alter the hh and i i are two Aat rods of iron or steel, about structure of the short arms of the levers, by half an inch wide and an eighth of an inch making them turn each on an axis of motion, thick each ; and k k is a rod of zinc, of nearly a and to change their places of pressure mutually, quarter of an inch thick, interposed; the two exin order that their united action may be applied treme or iron rods are cranked, one at the top in the same point, at the centre of the brass bar, to receive the suspension spring, and the other in direct opposition to the line of downward ex. at the bottom to hold the ball in the same verpansion. See his Elements, p. 106, and plate xi. tical line with the zinc rod. These three parallel Mr. Hardy of Clerkenwell has also improved rods are united by four screws, 1, 1, 1, l, which, considerably Elliott's pendulum.

passing through oblong holes in the bars h h and Mr. Troughton's mercurial pendulum.-- This is k k, screw into the rod i i, while the rod hh is an improvement on Graham's mercurial pendu- fastened to the zinc one k k, by the single screw lum. About the year 1790 Mr. Edward Trough- m near its lower extremity, which screw is the ton, with a view of doing away the most mate- screw of adjustment for temperature, and rerial prejudice against this useful instrument, quires several holes to be made in the bar kh, contrived a modification of the mercurial pen- and also in k k, that the length of the zinc bar dulum, which must be considered as a distinct may be limited to its due proportion for exact invention; the materials being differently ar- compensation. The iron bar i i rests by a chinranged both as to quality, quantity, and situation. piece on the upper end of the zine bar, and The prejudice alluded to was that the metallic therefore the ball supported by its lower tapped rod of Graham, and the vessel of mercury, would end stretches all the bars equally. If the zinc not be affected by changes of temperature in a bar had rested on the crank at the bottom of the contemporaneous manner, but that the mercury bar hh, instead of being held by the screw m, the being below the rod, and having on that account arrangement would have been the same as in a quicker motion, would cool sooner than the Deparcieux's, but with zinc substituted for brass, metallic rod, and be liable to more frequent which consequently does not require the aid of changes from its greater susceptibility. “Mr. a lever to increase its effect. The proportional Troughton therefore substituted a strong glass expansions of zinc and iron were taken for this tube with a bulb at the lower extremity, to be pendulum from Smeaton's table in the fortyfilled to a certain height with mercury, which eighth volume of the Phil. Trans. of London, and should rise and fall precisely as in a thermome- were made for hammered zinc as 373 : 151; but

.. which instrumeni, in fact, his tube is; and, subsequent abservations on the rate of the clock, to which the pendulum was applied, proved that ball is heavy, as is now customary in seconds' the expansion of the hammered zinc was greater pendulums, its weight will place a great stress than Smealon's table gives it, though the quan- on the slender springs that connect it with the lity was within the reach of the adjustment. verge, and produce, probably, a vacillation, as

Reid's compensation pendulum. - Another com- in Doughty's, that must be very unfavorable to pensation pendulum by Mr. Adam Reid of isochronism, allowing even that the compensaWoolwich was also presented to the Society of tion is perfect. To avoid this evil Mr. NicholArts in April 1809, and the inventor was reward- sun placed a similar compensation bar on the ed with fifteen guineas for bis contrivance. This cock of suspension above the verge of his penis given in fig. 4, plate II., and has its compen- dulum, and also above the cock of limitation, as sation of a tube of zinc acting on the ball from seen in fig. 6, but without any spring, and in the lower end of the steel verge thus : A B is the this situation the varying curvature of the horisteel verge, made a little thicker where it enters zontal compound bar, E E, altering the length of the ball C, and also of a lozenge shape, to pre- the suspension spring, produced the alternate vent the ball's turning, but above and below it rising and falling of the ball, as the verge carried is cylindrical; near the centre of the ball is a it in an opposite direction, so that the centre of shoulder in the verge, against which the upper oscillation was comparatively stationary. Sec end of the zinc tube D presses the cross piece Phil. Journal, vol. i. 4to. ed., plate V. fig. 3. of the ball when the nut E is turned up close to The same author also contrived a compensation its lower extremity, but when the nut is turned pendulum composed of four rods of steel and back, in adjusting for rate, the tube descends a one of a compound, or alloy, of zinc and silver, little, and the ball with it, while it rests on the which is described in vol. ij. of his 4to. Phil. upper extremity of the tube. When the com- Journal, p. 205, plate IX. pensation is too much the tube may be short- PENELOPE, in fabulous history, the daughter ened till it is found of the exact length, by a trial of Icarus, who married Ulysses, by whom she of the rate in extremes of temperature. In the had Telemachus. During the absence of Ulysfigure the length of the zinc tube does not ap- ses, who was gone to the siege of Troy, and who pear sufficiently long to compensate an entire staid twenty years from his dominions, several verge of steel. The inventor observes that pla- princes, charmed with Penelope's beauty, told tina might be substituted for steel, and steel for her that Ulysses was dead, offered to marry her, zinc, for the formation of this kind of pendulum, and pressed her to declare in their favor. She but that the expense would be enhanced by the promised compliance on condition they would dearness of platina.

give her time to finish a piece of tapestry she Ritchie's and Nicholson's compensation pendu- was weaving ; but at the same time she undid lum.-In March 1812 Mr. David Ritchie, of in the night what she had done in the day, and Clerkenwell, laid before the society a model of thus eluded their importunity until Ulysses's a compensation pendulum, for which he received return. twenty guineas. The compensation was effected PENELOPE, in ornithology, a genus of birds of by the flexure of two compound horizontal bars the order of gallinæ, the characters of which are interposed between the verge and the ball, which these : The beak is bare at the base; the head act on the same principle as the compound bars is covered with feathers; the neck is quite bare ; in the ordinary compensation balances of a chro- the tail consists of twelve principal feathers; and nometer. Fig. 5 represents the pendulum, in the

most part bare. Linné, in which A is the spring of suspension, B the ball, his Systema Naturæ, enumerates six species. and C the steel verge as usual, with the nut of 1. P. crax cumanensis, called by Latham, adjustment for rate at E, below the ball.

The &c., yacou.

It is bigger than a common fowl. compensating bars are F and G, the upper part The bill is black; the head feathers are long, of F and the lower part of G being steel, and the pointed, and form a crest, which can be erected other parts brass ; so that any additional heat at pleasure. The irides are of a pale rufous may bring the bars nearer together by the con- color; the space round the eye is naked, similar vexity of the brass faces of the compound bars to that of a turkey. It has also a naked membeing contiguous.. These compound bars have brane or kind of wattle, of a dull black color. each a sliding piece above and below, and f re- The blue skin comes forward on the bill, but is spectively, by the sliding of which the bars may not liable to change color like that of the turkey. have their effective lengths altered, in the adjust- The plumage has not much variation; it is chiefly ment for temperature; and are connected by the brown, with some white markings on the neck, slender springs e and f, which bear a portion of breast, wing coverts, and belly ; ihe tail is comthe ball's weight; the remainder being borne by posed of twelve feathers, pretty long, and even the springs l and m attached by screws at h, one at the end ; the legs are red. This species inhato the verge piece d and the other to the ball bits Cayenne, but is a very rare bird, being met piece b, while they themselves are united by with only in the inner parts, or about the Amascrews at I and m. The compensation frame, zons country, though in much greater plenty up so constructed, is adjusted by sliding the com- the river Oyapoc, especially towards Camoupi; pound bars, before they are fixed, till the centre and indeed those which are seen at Cayenne are of the ball falls in the vertical line of the verge, mostly tame ones; for it is a familiar bird, and where the screws at h fix it for trial. It has been will breed in that state, and mix with other feared that when the crutch of the clock urges poultry. It makes the nest on the ground, and the verge the ball will not move with it till the hatches the young there, but is at other times springs c and f'are hent a little ; for when the mostly seen on trees. Ii frequently erects the

are for

crest, when pleased or taken notice of, and like- bird has a singular construction, passing along wise spreads the tail upright like a fan, in the the neck to the entrance of the breast, where it manner of the turkey. It has two kinds of cry; arises on the outside of the flesh, and after going one like that of a young turkey, the other lower a little way downwards, returus, and, then passes and more plaintive; the first of these is thought into the cavity of the lungs. It is kept in its by the Indians to express the word couyovoit, place on the outside by a muscular ligament, the other yacou.

which is perceivable quite to the breast bone. 2. P. maralia, the marail, about the size of This is found to be the case in both male and female, a fowl, and shaped somewhat like it. The bill and plainly proves that it differs from the yacou, and irides are blackish; the space round the eye whose wind-pipe has no such circumvolution in is bare, and of a pale red; the chin, throat, aud either sex. If this be the bird mentioned by fore part of the neck are scarcely covered with Fermin, in his History of Guiana, p. 176, he says feathers; but the throat itself is bare, and the that the crest is cuneiform, and of a black and membrane elongated to half an inch or more; white color; and observes that they are scarce both this and the skin round the eyes change at Surinam; but it does not seem quite certain color, and become deeper and thicker when the whether he means this species or the yacou. bird is irritated. The head feathers are longish, Bancroft mentions a bird of Guiana by the name so as to appear like a crest when raised up, of marrodée, which he says is wholly of a brownwhich the bird often does when agitated; at which ish-black: the bill the same ; and the legs gray. time it also erects those of the whole body; and These he says are common, and make a noise not so disfigures itself as to be scarcely known. The unlike the name given it, perching on trees. The general color of the plumage is a greenish black; Indians imitate their cry so exactly as to lead the fore part of the neck is tipped with white; to the discovery of the place the birds are in, the wings are short; the tail is long, consisting by their answering it. The flesh of them is like of twelve feathers, which are even at the end, and that of a fowl: it is therefore most likely the commonly pendent, but can be lifted up, and marail. spread out like that of the turkey; the legs and 3. P. meleagris cristata, called by Ray penetoes are of a bright red; the claws are crooked, and lope jacupeme, and by Edwards the guan, or somewhat sharp. In a collection, says Latham, quan, is about the size of a fowl, being about from Cayenne was a bird, I believe, of this very two feet six inches long. The bill is two inches species. It was twenty-eight inches long; the long, and of a black color; the irides are of a bill is like that of a fowl, brown, and rather dirty orange color; the sides of the head are hooked; round the eyes bare ; the head is creste covered with a naked purplish blue skin, in ed; the feathers of the fore part of the neck are which the eyes are placed : beneath the throat, tipped with white; the breast and belly are rufous for an inch and a half, the skin is loose, of a brown; the rest of the plumage is greenish browa; fine red color, and covered only with a few hairs. the tail is eleven inches long, and rounded at the The top of the head is furnished with long feaend; the quills just reach beyond the rump;

the thers, which the bird can erect as a crest at plealegs are brown, and the claws hooked. This sure ; the general color of the plumage is brownspecies is common in the woods of Guiana, at a ish black, glossed over with copper in some distance from the sea, though it is less known lights; but the wing coverts have a greenish and than could be imagined; and generally found in violet gloss. The quills mostly incline to a pursmall flocks, except in breeding time, when it is ple color; the fore part of the neck, breast, and only seen by pairs, and then frequently on the belly, are marked with white spots; the thighs, ground, or on low shrubs; at other times on under tail coverts, and the tail itself, are brownish high trees, where it roosts at night. The female black; the legs are red; the claws black. Some makes her nest on some low bushy trees as near of these birds have little or no crest, and are the trunk as possible, and lays three or four eggs. thence supposed to be females. They inhabit When the young are hatched, they descend with Brasil and Guiana, where they are often made their mother, after ten or twelve days. The mo- tame. They frequently make a poise not unlike ther acts as other fowls, scratching on the ground the word jacu. Their Mesh is much esteemed. like a hen, and brooding the young, which quit 4. P. meleagris satyra, the horned pheasant. their nurse the moment they can shift for them- Latham calls it the horned turkey. This species selves. They have two broods in a year; one in is larger than a fowl, and smaller than a turkey. December or January, the other in May or June. The color of the bill is brown; the nostrils, foreThe best time of finding these birds is morning head, and space round the eyes are covered with or evening, being then met with on such high slender black hairy feathers; the top of the head trees whose fruit they feed on, and are discover- is red. Behind each eye there is a feshy callous ed by some of it falling to the ground. The blue substance like a born, which tends backyoung birds are easily tamed, and seldom forsake ward. On the fore part of the neck and throat the places where they have been brought up: there is a loose Aap of a fine blue color, marked they need not be boused, as they prefer the roost- with orange spots, the lower part of which is being on tall trees to any other place. Their cry is set with a few hairs ; down the middle it is inharmonious, except when irritated or wounded, somewhat looser than on the sides, being wrinkled. when it is harsh and loud. Their flesh is much The breast and upper part of the back are of a esteemed. Buffon supposes this bird to be the full red color. The neck and breast are inclined female of the yacou, or at least a variety; but to yellow. The other parts of the plumage and that this cannot be, the anatomical inspection tail are of a rufous brown, marked all over with will at once determine. The windpipe of this white spots, encompassed with black. The legs

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