believe the scripture to be God's word; to endeavour to find the true sense of it, and to live according to it."

Such are the genuine principles of Protestantism; such the spirit by which all christians ought to be actuated. Those men, who, calling themselves Protestants, are of a contrary spirit (and it is a lament able fact that their number is daily increasing) are a disgrace to their profession, and bring dishonour on the common cause of christianity. Their devotion is enthusiasm, and their zeal madness; while their increasing number portends one of the greatest of all public calamities; threatening to rekindle the latent embers of persecution;—again to light up those fires which the united efforts of reason, philosophy, and the principles of rational religion have conspired to extinguish for ever. See ARMINIANS, PRESBYTERIANS, PURITANS, REFORMATION, and ROMAN CA

THOLICS.

PROTESTATION is a form in pleading, when one does not directly affirm or deny any thing that is alleged by another, or which he himself alleges.

PROTRACTOR is the name of an instrument used for protracting or laying down on paper the angles of a field, or other figure. The protractor is a small semi circle of brass, or other solid matter, the limb or circumference of which is nicely divided into one hundred and eighty degrees: it serves not only to draw angies on paper, or any plane, but also to examine the extent of those already laid down. For this last purpose, let the small point in the centre of the protractor be placed above the angular point, and let the side coincide with one of the sides that contain the angle proposed; then the number of degrees cut off by the other side, computing on the protractor, will show the quantity of the angle that was to be measured. See MENSURATION.

Piotractors are now more usually made in the form of a parallelogram, and properly graduated at the upper edge. See MATHEMATICAL Instruments.

PROVIDENCE, the conduct and direction of the several parts of the universe, by a superior intelligent being.

PROVINCE, in law, means the circuit of an Archbishop's jurisdiction, which is subdivided into bishoprics. The ecclesiastical division of this kingdom is into two provinces; riz. Canterbury and York. Proyincial constitutions, in this kingdom, were

decrees made in the provincial synods, held under divers Archbishops of Canterbury.

PROVISO, in law, is a condition inserted in a deed, upon the observance of which the validity of the deed depends.

PROVOST marshal, an officer of the King's navy, who has charge of the King's prisoners taken at sea.

PROVOST, or PREVOT, in the King's stables; his office is to attend at court, and hold the King's stirrup, when he mounts his horse, &c. There are four provosts of this kind, each of whom attends in his turn monthly.

PROW, in navigation, denotes the head or fore-part of a ship, particularly in a galley, being that which is opposite to the poop or stern. In the middle of the prow is the beak that cuts the water, on the top of which is commonly some figure or hieroglyphic. The prow is lower than the poop, and contains fewer decks.

PRUNELLA, in botany, self-heal, a genus of the Didynamia Gymnospermia class and order. Natural order of Verticillatæ, or Labiatæ. Essential character: filaments forked, with an anther on one of the forks; stigma bifid. There are three species.

PRUNELLA, sal,in pharmacy,a preparation of purified saltpetre, called also crystal mineral, made in this manner: having melted any quantity of saltpetre, cast a little flow ers of sulphur upon it, and when that is burnt throw on more; and continue to do so till the nitre flow as clear as rock-water. Then with a clean iron or brass ladle take it out, and, putting it into moulds till coagulated, preserve it for use.

PRUNING, in gardening and agricul ture, is the lopping off the superfluous branches of trees, in order to make them bear better fruit, grow higher, or appear more regular. Pruning, though an operation of very general use, is nevertheless rightly understood by few; nor can it be learned by rote, or, indeed, wholly by books, but requires a strict observation of the different manners of growth of the several sorts of fruit trees; the proper method of doing which cannot be known, without carefully observing how each kind is naturally disposed to produce its fruit ; for some do this on the same year's wood, as vines; others, for the most part, upon the former year's wood, as peaches, nectarines, &c. and others, upon spurs which are produced upon wood of three, four, &c. to fifteen or twenty years old, as pears, plumbs, cher

sic. When, therefore, the test is exposed to the air, the carbonic acid, which the atmosphere always contains, assisted by the affinity between the yellow prussiate and the prussic acid, decomposes the prussiate of potash in the test, and the yellow prussiate is precipitated in the form of Prussian blue, and every other acid produces the same effect. A test of this kind would indicate the presence of iron in every mixture which contains an acid (for a precipitation of Prussian blue would appear), and could not therefore be employed with any confidence.

PRUSSIC acid, in chemistry and the arts, is one of the most important of the acids. It was discovered by accident about the beginning of the last century by Diesbach, a chemist of Berlin. This gentle man, wishing to precipitate a decoction of cochineal with an alkali, got some potash on which he had distilled several times his animal oil, and as there was some sulphate of iron in the decoction, the liquor instantly exhibited a beautiful blue in the place of a red precipitate. Hence he saw the method of producing the same substance at pleasure, and it soon became an object of commerce, and obtained the name of Prussian blue, from the place where it was discovered. This substance is now formed, chiefly, during the decomposition of animal substances in high temperatures. Three parts of blood, evaporated to dryness in an iron dish, are to be mixed with one part of snbcarbonate of potash (common pearlash), and calcined in a crucible, which should be only two-thirds filled by the materials, and covered with a lid. The calcination must be continued, with a moderate heat, as long as a blue flame issues from the crucible; and when it becomes faint, and likely to be extinguished, the process must be stopped. Throw the mass, when cold, into ten or twelve parts of water; allow it to soak a few hours, and then boil them together in an iron kettle. Filter the liquor, and continue pouring hot water on the mass as long as it acquires any taste. To this solution add one composed of two parts of alum and one of sulphate of iron, in eight or ten of boiling water, and continue the mixture as long as any effervescence and precipitation ensues. Wash the precipitate seve ral times with boiling water. It will have a green colour; but, on the addition of a quantity of muriatic acid, equal to twice that of the sulphate of iron which has been

used, it will assume a beautiful blue colour. Wash is again with water, and dry it in a gentle heat. In this state it is the pigment, called Prussian blue, which consists of a mixture of prussiate of iron with alumine. From prussiate of iron, the prussic acid may be separated by the following process: mix two ounces of red oxide of mercury, prepared by nitric acid, with four ounces of finely powdered Prussian blue, and boil the mixture with twelve ounces of water in a glass vessel, shaking frequently. Filter the solution, which is a prussiate of mercury, while hot, and when cool, add to it, in a bottle, two ounces of iron filings, and six or seven drachms of sulphuric acid; shake these together, decant the clear liquor into a retort, and distil off one-fourth of the liquor. The distilled liquor is the prussic acid, which combines with alkalies and earths, and has many of the properties belonging to the other acids. It has a sweetish taste, and a smell resembling that of bitter almonds; it does not redden blue vegetable colours. It precipitates sulphurets, and curdles soap. It separates alumine from nitric acid. Oxygenized muriatic acid entirely decomposes it. It does not appear to have a strong affinity for alkalies, nor does it take them from carbonic acid, for no effervescence arises on adding it to a solution of alkaline carbonates; on the contrary, its combinations with alkalies and earths are decomposed by exposure to carbonic acid, even when highly diluted, as in atmospheric air. It readily combines, however, with pure alkalies, destroys their alkaline properties, and forms crystallizable salts. It does not precipitate iron blue, but green, and this green precipitate is soluble in acids. The rays of light render the green precipitate blue, as docs also the addition of metallic iron, or sulphurous acid.

PSIDIUM, in botany, guava, a genus of the Icosandria Monogynia class and order. Natural order of Hesperidæ. Myrti, Jussieu. Essential character: calyx fivecleft superior; petals five; berry one-celled, many-seeded. There are eight species, natives of the East and West Indies.

PSITTACUS, the parrot, in natural history, a genus of birds of the order Pica. Generic character: bill hooked, upper mandible moveable; nostrils round in the base of the bill, and sometimes covered with a cere; tongue fleshy, broad, and blunt at the end; head large, crown flat; toes formed

for climbing. These abound within the tropics, and live on seeds and fruits in their natural state, but in confinement will eat both flesh and fish. They often appear in flocks, yet are in such cases generally somewhat separated into pairs. They are noisy, mimetic, singularly capable of articulating human sounds, extremely docile and long lived. They breed in the hollows of trees, without constructing any nest, and use their feet as hands to convey food to their mouths, Latham notices one hundred and thirty-three species, and Gmelin no fewer than one hundred and sixty nine. The general division is regulated by the evenness or unevenness of the tails. The following are the principal species.

P. macao, or the red and blue maccaw, is as large as a capon, and inhabits South America. With its bill it breaks a peachstone with the most perfect ease. These birds lay their eggs in decayed trees, and often enlarge the hollow for this purpose with their bills. They are used for food in vast numbers in Cayenne. They are, in common with many species, exposed to fits when confined.

P. rufirostris, or the long-tailed green parrakeet, is of the size of a blackbird, extremely clamorous, and highly imitative. These birds are seen in large flocks, and alighting on certain trees, can with difficulty be distinguished, in consequence of the similar colour of their plumage to that of the leaves. They inhabit various parts of America, are used for food, and are extremely fat. The above have tails uneven at the end.

P. Melaccensis, or the Molucca cockatoo, inhabits the Moluccas, is about fifteen inches long, and is regarded by Buffon as one of the most docile and interesting birds of the tribe.

P. pullarius, or the red headed Guinea parrakeet, is of the size of a lark, and is extremely common in many parts of Africa. These birds are peculiarly distinguished by their mutual affection. They are exported from Africa in considerable numbers for their beauty and attachment, and not on account of any power of articulation or enchantment of melody, their sounds being harsh and grating. Few, however, survive the voyage. They are kept in cages, in pairs, and the attentions of the male to the female are highly tender, elegant, and interesting. He extricates the seeds from their husks, and presents them to her in this prepared state, and appears restless and misera

ble on the slightest separation. Indeed the attachment is reciprocal, the sadness of one always producing distress in the other; and the death of either involving the survivor, generally, in fatal as well as fruitless grief.

PSOPHIA, the trumpeter, in natural history, a genus of birds of the order Gralla. Generic character: bill cylindrical, conic, convex; nostrils oval, sunk, and pervious; tongue cartilaginous, flat, and fringed at the tip; feet four-toed and cleft. Latham mentions only one species, riz. P. crepitans, or the gold-breasted trumpeter, is of the size of a large fowl, and very high on its legs, and abounds in South America, especially in the country of the Amazons. It is remarkable for emitting from its lungs a noise very similar to the sound of a child's trumpet, and, being easily domesticated, will often follow the person to whose care it is committed through the streets, making this singular noise. It may be fed on bread and fish. It runs fast, aided by the expansion of its wings. When confined with poultry it often annoys both common fowls and turkeys, and, indeed, occasionally, destroys them. It will follow the Negroes in the West Indies, and catch at their legs, not unfrequently producing blood. Their flesh is esteemed a considerable delicacy.

PSORALEA, in botany, a genus of the Diadelphia Decandria class and order. Natural order of Papilionacea or Leguminosæ. Essential character: calyx besprinkled with callous dots, the same length with the legume, which has only one seed in it. There are thirty-three species, chiefly natives of the Cape of Good Hope.

PSYCHOTRIA, in botany, a genus of the Pentandria Monogynia class and order. Natural order of Stellatæ. Rubiacea, Jussien.

Essential character: calyx fivetoothed, crowning; corolla tubular; berry globular; seeds two, hemispherical, grooved. There are thirty-nine species.

PTELEA, in botany, a genus of the Tetrandria Monogynia class and order. Natural order of Terebintaceæ, Jussieu. Esscatial character: calyx four parted, inferior; corolla four-petalled; stigmas two; fruit with a roundish membrane, having one seed in the middle. There is but one species, viz. P. trifoliata, three leaved ptelea, or shrubby trefoil, a native of North America.

PTERIS, in botany, a genus of the Cryptogamia Filices class and order. Natural order of Filices or Ferns. Generic charac