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“ April 26th, in the evening, at nine is to be held, that none may be surprised, o'clock, true time, I succeeded in effect. but that all may have full time before, to ing the measurement of Vesta, with the consider of what is to be proposed at the same power of 238, by means of the meeting. thirteen feet reflector, with whicb that of VESUVIAN, in mineralogy, a species Ceres, Pallas, and Juno, liad been made; of the Flint genus; it is of a dark oliveand when viewed by this reflector, it also green, which passes into a blackish green. appeared exactly in the same manner. It occurs massive, often crystallized. Of several illuminated disks, of 2.0 to Specific gravity about 3.5. Before the 0.5 decimal lines, which I had before blow-pipe, it melts, without addition, into made use of for measuring the satellites a yellowish and faintly translucent glass. of Saturn and Jupiter, the smallest disk It is found among the exuviæ of Vesu. only of 0.5 lines could be used for this vius, in a rock composed of mica, hornpurpose ; by it the rounded nucleus of blende, garnet, and calx spar,which Werthe planet Vesta, when the disk was at ner imagines to constitute part of the prithe distance of 611.0 lines from the eye, mitive mass on which that volcanic moun. appeared almost of the same size, and í tain rests. It has also been found in Sibe. must even estimate its diameter as one- ria, and in Kamtschatka. At Naples it is sixth smaller. If, therefore, we attend, cut into ring stones, and is sold under not to the full magnitude of the projec. various names. Two specimens have been tion, but the estimation just mentioned, analyzed by Klaproth; the results are as it follows, by calculation, that the appa- follow : rent diameter of the planet Vesta is only

Vesuvian of Vesuvius. 0.488 seconds, and, consequently, only Silica

35.50 half of what I have found to be the appa

Lime

33 00 rent diameter of the fourth satellite of Alumina

22.25 Saturn. This extraordinary smallness, Oxide of Iron

7.50 with such an intense, radiant, and un. Oxide of manganese

0.25 steady light of a fixed star, is the more

Loss

1.50 remarkable, as according to the preliminary calculations of Dr. Gauss, there

100.00 can be no doubt that this planet is found in the same region between Mars and Ju.

Vesuvian of Siberia. piter, in which Ceres, Pallas, and Juno, Silica

42.00 perform their revolutions round the sun ; Lime

34.00 that, in close union with them, it has the

Alumina

16 25 same cosmological origin; and that, as a Oxide of Iron

5.50 planet of such smallness and of so very

Loss

2.25 intense light, it is comparatively near to the earth. This remarkable circumstance

100.00 will no doubt be productive of important cosmological observations, as soon as the elements of the new planet have been

VESUVIUS, a famous volcano, or sufficiently determined, and its distance burning mountain, situate only six miles from the earth ascertained by calcula- east of the city of Naples, in Italy. See tion."

VOLCANO. Much of what is said of Vesta is appli- VIBRATION, in mechanics, a regular cable to the other small planetary bodies reciprocal motion of the body,as, for examreferred to in this article.

ple, a pendulum, which, being freely susVESTRY, a place adjoining to a church, pended, swings or vibrates from side to where the vestments of the minister are side. Mechanical authors, instead of vikept ; also a meeting at such place, where bration, often use the term oscillation, the minister, churchwardens, and princi- especially when speaking of a body that pal men of most parishes, at this day, thus swings by means of its own gravity or make a parish vestry. On the Sunday be. weight. fore a vestry is to meet, public notice The vibrations of the same pendulum ought to be given, either in the church, are all isochronal; that is, they are per. or after divine service is endedi, or else at formed in an equal time, at least in the the church door, as the parishioners come

same latitude; for in lower latitudes they out, both of the calling of the meeting, are found to be slower than in higher and also the time and place of the assem

See PENDULUM In our latitude bling of it; and it is reasonable then also a pendulum 394 inches long vibrates seto declare for what business the meeting conds, making 60 vibrations in a minute.

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The vibrations of a longer pendulum VIBURNUM, in botany, laurustinus, a take up more time than those of a shorter genus of the Pentandria Trigynia class one, and that in the subduplicate ratio of and order. Natural order of Dumosæ. the lengths, or the ratio of the square Caprifolia, Jussieu. Essential character: roots of the lengths Thus, if one pendu. calyx five-parted, superior ; corolla five. lum be 40 inches long, and another only cleft; berry one-seeded. There are twen10 inches long, the former will be double ty-three species. the time of the latter in performing a vi- VICAR, one who supplies the place of bration; for ✓ 40: ✓ 10 :: 4:1, another. The priest of every parish is call. that is, as 2 to 1. And because the num- ed rector, unless the prædial tithes are ber of vibrations, made in any given time, appropriated, and then he is styled vicar; is reciprocally as the duration of one vi and when rectories are appropriated, vibration, therefore the number of such vi- cars are to supply the rector's place. For brations is in the reciprocal subduplicate the maintenance of the vicar, there was ratio of the lengths of the pendulums. then set apart a certain portion of the VIBRATIONS of a stretched chord, or

tithes, commonly about a third part of the string, arise from its elasticity; which whole, which are now what are called power being in this case similar to gravi.

the vicarial tithes, the rest being reserved

to the use of those houses, which for the ty, as acting uniformly, the vibrations of a chord follow the same laws as those of like reason are termed the rectorial tithes.

VICARAGE. For the most part vicarpendulums. Consequently, the vibrations of the same chord, equally stretched,

ages were endowed upon appropriations : though they be of unequal lengths, are

but sometimes vicarages have been enisochronal, or are performed in equal

dowed without any appropriation of the times; and the squares of the times of parsonage; and there are several church

es where the tithes are wholly improprivibration are to one another inversely as their tensions, or powers by which they ated, and no vicarage endowed; and there are stretched. The vibrations of a spring,

the impropriators are bound to maintain too, are proportional to the powers by

curates, to perform divine service, &c. which it is bent. These follow the same

The parsons, patron, and ordinary, may laws as those of the chord and pendulum ;

create a vicarage, and endow it; and in and conse ently are isochronal, which is

time of vacancy of the church, the patron the foundation of spring-watches.

and ordinary may do it ; but the ordinary

alone cannot create a vicarage, without VIBRATions are also used in physics, the patron's assent. &c. and for several other regular alter

VICE, in smithery, and other arts emnate motions. Sensation, for instance, is ployed in metals, is a machine or instrusupposed to be performed by means of ment, serving to hold fast any thing they the vibratory motion of the contents of

are at work upon, whether it is to be filed, the nerves, begun by external objects, bent, riveted, &c. To file square, it is aband propagated to the brain. This doc- solutely necessary that the vice be placed trine has been particularly illustrated by perpendicular, with its chaps parallel to Dr. Hartley, who has extended farther

the work-bench. than any other writer, in establishing a Vice, hand, is a small kind of vice, new theory of our mental operations. The serving hold the lesser works in that same ingenious author also applies the require often turning about. Of these doctrine of vibrations to the explanation there are two kinds: the broad chapped of muscular motion, which he thinks is

hand vice, which is that commonly used; performed in the same general manner as and the square nosed hand-vice, seldom sensation and the perception of ideas. For

used but for filing small round work. a particular account of his theory, and the

Vice is also a machine used by the arguments by which it is supported, see

glaziers to turn or draw lead into fat bis “ Observations on Man," vol. i.: see

rods, with grooves on each side to receive also Belsham's “ Elements;" and " In

the edges of the glass. troductory Essays to Hartley,” by Dr. Vice is also used in the composition of Priestley

divers words, to denote the relation of VIBRIO, in natural history, a genus of something that comes instead, or in the the Vermes Infusoria class and order. place, of another; as vice admiral, vice. Worm invisible to the naked eye, very chancellor, vice-chamberlain, vice-presi. simple, round, elongated. There are

dent, &c. are officers who take place in twenty species, described by Adams, and the absence of admirals, &c. See the ar. other authors on the microscope.

ticle ADMIRALS, &c.

VICIA, in botany, vetch, a genus of the with the construction and use of the same. Diadelphia Decandria class and order. To this complete treatise on trigonomeNatural order of Papilionaceæ, or Legu. try, plane and spherical, are subjoined minosæ. Essential character: stigma several miscellaneous problems and obtransversely bearded on the lower side. servations, such as the quadrature of the There are twenty-five species.

circle, the duplication of the cube, &c. VICINAGE, in law, common of vici- Computations are here given of the ratio nage is, where the inhabitants of two of the diameter of a circle to the circumtownships, which lie contiguous, have ference, and of the length of the sine of usually intercommoned with one another, one minute, both to a great many places the beasts of the one straying mutually of figures : by which he found that the into the other's fields without any moles. sine of one minute is tation from either. This, indeed, is only a permissive right, intended to excuse

between 2908881959 what, in strictness, is a trespass in both,

and 2908882056 and to prevent a multiplicity of suits; and therefore either township may inclose. also the diameter of a circle, being 1000, and bar out the other, though they have &c. that the perimeter of the inscribed intercommoned time out of mind Neither and circumscribed polygon of 393216 has any person of one town a right to put sides will be as follows, viz. the his beasts, originally, into the other's common; but if they escape and stray Perimeter of the inscribthere of themselves, the law does not ed polygon

}31415926535 punish trespass.

Perimeter of the circumVI ET ARMIS, with force and arms, in scribed polygon.

}31415926537 law, are words used in indictments, declarations, &c. to express the charge of and that therefore the circumference of forcible and violent committing any crime the circle lies between those two num. or trespass; but on appeal of death, on a bers. killing with a weapon, the words vi et ur. Vieta was also a profound decipherer, mis are not necessary, because they are an accomplishment that proved very use. implied; so an indictment of forcible ful to his country. As the different parts entry alleged to have been made manu of the Spanish monarchy lay very distant forti, &c.

from one another, when they had occaVIETA, (Francis,) in biography, a sion to communicate any secret designs, very celebrated French mathematician, they wrote them in ciphers and unknown was born in 1540, at Fontenai, a province characters, during the disorders of the of France. Among other branches of league: the cipher was composed of learning in which he excelled, he was one more than 500 different characters, which of the most respectable mathematicians yielded their hidden contents to the peof the sixteenth century, or indeed of any netrating genius of Vieta alone. His skill age. His writings abound with marks of so disconcerted the Spanish councils for great originality, and the finest genius, two years, that they published it at Rome, as well as intense application. His appli- and other parts of Europe, that the cation was such, that, it is said, he has French King had only discovered their sometimes remained in his study for three ciphers by means of magic. He died at days together, without eating or sleep. Paris, in the year 1603, in the sixty-third ing. His inventions and improvements, year of his age. in all parts of the mathematics, were very VIEW, in law, is generally where a considerable. He was in a manner the real action, or an action of trespass, is inventor and introducer of specious alge. brought in any of the courts of record at bra, in which letters are used instead of Westminster, and it shall appear to the numbers. He made also considerable court to be proper and necessary that the improvements in geometry and trigono. jurors should have a view, they may or. metry. He gave some masterly tracts on der special writs of distringas or habeas trigonometry, both plane and spherical, corpora to issue, commanding the sheriff which may be found in the collection of to have six of the first twelve of the juhis works, published at Leyden in 1646, rors therein named, or of some greater by Schooten, besides another large and number of them, at the place in question, separate volume in folio, published in the &c. This is done where it is of any im. author's life-time, at Paris, in 1579, con- portance to the determination of the taining extensive trigonometrical tables, cause, to be acquainted with the local

situation and actual state of the place in through the intermedium of vinous ferjured.

mentation. Both these methods are acVILLAIN, or VILLEIN, in our ancient tually practised with complete success. customs, denotes a man of servile and To make vinegar out of a liquor contain. base condition, viz. a bondman or ser- ing suitable materials, it is only necessavant: and there were anciently two sorts ry, 1st, to allow some access of air to the of bondmen or villains in England : the vessel in which it is kept; and 2d, to keep one termed a villain in gross, who was it in a temperature rather higher than that immediately bound to the person of his of the atmosphere in this climate, that is lord and his heirs: the other a villain re. to say, about 750 to 80°. It is also al. gardent to a manor, he being bound to most essential, where a liquor already fer. his lord as a member belonging and an. “mented is employed, to add a portion of nexed to the manor whereof the lord was yeast, or any other ferment; for though owner; and he was properly a pure vil. any fermented liquor, if kept in a modelain, of whom the lord took redemption rate temperature in an open vessel, will to marry his daughter, and to make him spontaneously run sour, or become changfree ; and whom the lord might put out ed to vinegar, this change is too gradual of his lands and tenements, goods and to produce this aciden perfection, and the chattels, at his will, and beat and chastise, first acetified portion turns mouldy before but not maim him.

the last has be ome sour: but where the VINCULUM, in algebra, a mark or substance employed has not yet under. sharacter, either drawn over, or including, gone fermentation, the whole process of or some other way accompanying, a fac. the vinous and subsequent acetous fer. tor, divisor, dividend, &c. when it is com- mentation will go on uninterruptedly with pounded of several letters, quantities, or the same ferment which at first set it in terms, to connect them together as one action, which happens, for example, in quantity, and show that they are to be the making vinegar from malt, or from multiplied or divided, &c. together. Vi. sugar and water. In this country vinegar eta first used the bar or line over the quan- is chiefly made from malt. The followtities for a vinculum, thus a + b; and ing is the usual process in London: A Albert Girard the parenthesis, thus mash of malt and hot water is made,

which, after infusion for an hour and a (a + b); the former way being now chiefly used by the English, and the lat. half, is conveyed into a cooler, a few ter bý most other Europeans. Thus

inches deep, and thence, when sufficient.

ly cooled, into large and deep fermenting a tū x c, or (a + b) X c, denotes tuns, where it is 'mixed with yeast, and the product of c and the sum a + b con

kept in fermentation for four or five days. sidered as one quantitity. Also a + b, The liquor, (which is now a strong ale or V (a+b), denotes the square root without hops) is then distributed into of the sum a+b. Sometimes the mark smaller barrels, set close together in a : is set before a compound factor as a stoved chamber, and a moderate heat is vinculum, especially when it is very long, kept up for about six weeks ; during or an infinite series: thus 3a X:1-2x which the fermentation goes on equally 4x3 + 535, &c.

and uniformly till the whole is soured. VINE. See VITIS.

This is then emptied into common barrels, VINCA, in botany, periwinkle, a genus which are set in rows (often of many hun. of the Pentandria Monogynia class and dreds) in a field in the open air, the bung. order. Natural order of Contortæ. Apo. hole heing just covered with a tile, to cinæ, Jussieu. Essential character: con- keep off the wet, but to allow a free ad. torted; follicles two, erect: seeds naked. mission of air. Here the liquor remains There are five species.

for four or five months, according to the VINEGAR is a liquor of an agreeable heat of the weather, a gentle fermentasmell, a pleasant and strongly acid taste, tion being kept up till it becomes perfect and of a hue varying from light-red to vinegar. This is finished in the following brown-straw colour; and is prepared by way: Large tuns are employed, with a fermenting any substance or compound false bottom, on which is put a quantity which has already undergone the spiritu- of the refuse of raisins, or other fruit, left ous fermentation.

Vinegar, therefore, by the makers of raisin and other home. may be made immediately from any wine, made wines, called technically rape, malt liquor, cider, &c.; or from the juicé These rape-tuns are worked by pairs ; of the grape and other fruits; from infu- one of them is quite filled with the vinegar sion of malt, or any saccharine liquid, from the barrels, and the other only

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TIA, &c.

three-quarters full, so that the fermenta. Natural order of Rubiacex, Jussieu. Estion is excited more easily in the latter sential character: calyx five-toothed, with than the former; and every day a portion teeth interposed; corolla funnel-form ; of the vinegar is laded from one to the stigma two-parted; capsule one-celled, other, till the whole is completely finish. many-seeded, inferior. There are two ed, and fit for sale. Vinegar, as well as species, viz V. biflora, two-flowered vi. fruit-wines, is often made in small quan- recta ; and V pratensis. tity for domestic uses, and the process is VIRGO, in astronomy, one of the signs by no means difficult. The materials may or constellations of the zodiac, and the be either brown sugar and water alone, or sixth according to order. It is marked sugar with raisins, currants, and especial. thus me, and in Ptolemy's catalogue conly ripe gooseberries: these should be sists of thirty-two stars, in Tycho's of mixed in the proportions which would thirty-nine, and in the Britannic of eighty. give a strong wine, put into a small bar. nine. rel, which it should fill about three

VIRTUAL focus in optics, is a point in fourths, and the bung-hole very loosely the axis of a glass, where the continuation stopped. Some yeast, or, what is better, of a refracted ray melts it. a toast sopped in yeast, should be put in,

VIS, a Latin word, signifying force or and the barrel set in the sun in summer, or a little way from a fire in winter, and power; adopted by physical writers to

divers kinds of natural powers or the fermentation will soon begin. This faculties. Vis impressa is defined, by Sir should be kept up constant, but very mo

Isaac Newton, to be the action exercised derate, till the taste and smell indicate

on any body, to change its state, either that the vinegar is complete. It should in resisting, or moving uniformly in a be poured off clear, and bottled carefully; right line. This force consists altogether and it will keep much better if it is boiled in the action, and has no place in the bofor a minute, cooled, and strained before dy, after the action is ceased. See Inerbottling. Vinegar contains a considerable quantity of colouring extractive mat

VISCUM, in botany, misseltoe, a genus ter from which it can only be freed by of the Dioecia Tetrandria class and order. distillation ; the process of which will Natural order of Aggregatæ. Linnæus. be clearly understood by a reference to Caprifolia, Jussieu. Essential character: the article DISTILLATION. See also

male, calyx four-parted; corolla none; Acetic acid. When vinegar is long kept, filaments none; anthers fastened to the especially exposed to the air, it becomes calyx : female, calyx four-leaved, supemuddy, acquires a mouldy, unpleasant rior: corolla none ; style none ; berry smell, loses its clear red colour and all one-seeded; seed cordate. There are its properties, and, finally, is changed to

twelve species. a slimy mucilage and water.

VISIBLE, something that is an object VIOL, in music, a stringed instrument,

of sight or vision, or something whereby resembling in shape and tone the violin,

the eye is affected, so as to produce a of which it was the origin.

sensation. VIOLA, in botany, violet, a genus of the

The Cartesians say that light alone is Syngenesia Monogamia class and order.

the proper object of vision. But, accordNatural order of Can naceæ. Cisti

, ing to Newton, colour alone is the proper Jussieu. Essential character: calyx five.

object of sight; colour being that proleaved; corolla five-petalled, irregular, perty of light, by which the light itself is horned at the back; anthers cohering; visible, and by which the images of capsule superior, one-celled, three-valv.

opaque bodies are painted on the retina. ed. There are forty-three species. Some

Philosophers in general had formerly of these plants are highly esteemed, par. taken for granted, that the place to which ticularly the V. odorata, sweet violet, for the eye refers any visible object, seen by its fragrance; it is a native of every part reflection or refraction, is that in which of Europe, in woods, among bushes, in

the visual ray meets a perpendicular hedges, and on warm banks, flowering

from the object upon the reflecting or the early in the spring.

refracting plane. That this is the case VIOLIN. See MUSICAL iustruments. with respect to plane mirrors is univer. VIOLONCELLO. See Musical instru- sally acknowledged ; and some experi

ments with mirrors of other forms seem VIPERSee COLUBER.

to favour the same conclusion, and thus VIRECTA, in botany a genus of the afford reason for extending the analogy Pentandria Monogynia class and order. to all cases of vision. If a right line be

ments.

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