P R A ( 672 ) P R M

Spaniards extended it to Naples , and thpTrench caught it during the siege of thelatter place in 1495; and from France it was rapidly spread over the rest ofEurope ; so that its original nursery, onthis side of the Atlantic, seems to havebeen a camp.

POZZUOLANA, an earth of a red-dish colour, which is used in Italy inlieu of sand, and when mixed with lime,makes excellent mortar that grows hardin water.

PRACTICABLE, a word frequentlyused in military matters, to express thepossible accomplishment of any object.Hence, “ a practicable breach.”

PRACTICE, or Gun-practice. In thespring, as soon as the weather permits,the exercise of the great guns begins, forthe purpose of shewing the gentlemencadets at the royal military academy atWoolwich, and the private men, themanner of laying, loading, pointing, andfiring the guns. Sometimes instrumentsare used to find the center line, or twopoints, one at the breech, the other atthe muzzle, which are marked with chalk,and whereby the piece is directed to thetarget; then a quadrant is put into themouth, to give the gun the required ele-vation, which, at first, is guessed at,according to the distance the target isfrom the piece. When the piece hasbeen fired, it isspunged, to clear it fromany dust or sparks of fire that may re-main in the bore, and loaded; then thecenter line is found, as before; and ifthe shot went too high, or too low, tothe right or to the left, the elevation andtrail are altered accordingly. This prac-tice continues morning and evening forabout six weeks, more or less, accor-ding as there is a greater or less numberof recruits. In the mean time, othersare shewn the motions of quick firingwith field pieces.

ikforJar-pRACTicE is generally exe-cuted in the following manner: a line of1500 or 5J000 yards is measured in anopen spot of ground, from the placewhere the mortars stand, and a flag fixedat about 300 or 500 yards: this beingdone, the ground where the mortars areto be placed is prepared and levelledwith sand, so that they may lie at anelevation of 45 degrees; then they areloaded with a small quantity of pow-der at first, which is increased afterwardsby an ounce every time, till they areloaded with a full charge: the times of;

the flights of the shells are observed, todetermine the length of the fuzes.—Theintention of this practice is, when amortar-battery is raised in a siege, toknow what quantity of powder is re*quired to throw the shells into the worksat a given distance, and to cut thefuzes of a just length, that the shellmay burst as soon as it touches theground.

Practice-Boo/c. See Book.

To PRACTISE, in a military sense,to go through the manual and platoonexercises, or through the various ma-noeuvres, &c. for the purpose of be-coming thoroughly master of militarymovements. Hence, to practise thenineteen manoeuvres. Practise is like-wise used, in imitation of the French , tosignify ihe act of effecting or executingany military operation, viz. to practisea mine beneath the covert wav, &c.

PILEFECTU1LE, Lat. During thetime of the Romans, there were certainconquered cities in Italy , which wereexclusively governed by Roman magis-trates whose laws and regulations theywere obliged to obey. These magistrates,were called prafecti. In imitation ofthe Romans, the modern French es-tablished what they named prefecturesand prefets. It also signifies, accordingto Adam Littleton, a lieutenancy, orcaptainship, or place of rule ; a govern-ment, a district, a province, or place ofjurisdiction. See also Lexicon Militate.

PIliEFECTUS, Lat. See Prefect.

Pr.eff.ctus Ca$trorum> Lat. an officeramong the Romans, whose rank and si-tuation correspond with those of a Marc-chal de camp in the French service, anda quarter-master general in the British .

pRiEFECTUS Classis, Lat. the comman-der in chief of a naval armament amongthe Romans. Ilis command lasted oneyear.

pRAiFECTUS Lr&tovii, Lat. the pre-fect, or chief officer in command, in theRoman praetorian bands, w ho had chargeof the emperor’s person ; and who, froma very circumscribed situation, graduallyrose into the most important stations.

PR./ETOR, Lat. After the expulsionof the kings, the consul was, at first, socalled among the Romans. He possess-ed kingly power both for civil and mili-tary affairs. Adam Littleton . See alsoLexicon MUilare.

FRiKTGRIANA CASTRA, IM. themain guard.