philology, the purloining another man's works, and putting them off as our own. Among the Romans, plagiarius was properly a person who bought, sold, or retained a freeman for a slave; and was so called, because, by the Flavian law, such persons were condemned ad plagas, "to be whipped."

Thomasius has an express treatise De plagio literario; wherein he lays down the laws and measures of the right which authors have to one another's writings.—"Dictionary-writers, at least such as meddle with arts and sciences, (as is pertinently observed by Mr Chambers), seem exempted from the common laws of meum and tuum; they do not pretend to set up on their own bottom, nor to treat you at their own cost. Their works are supposed, in great measure, compositions of other peoples'; and what they take from others, they do it avowedly, and in the open sun.—In effect, their quality gives them a title to everything that may be for their purpose, wherever they find it; and if they rob, they do not do it any otherwise, than as the bee does, for the public service. Their occupation is not pillaging, but collecting contributions; and if you ask them their authority, they will produce you the practice of their predecessors of all ages and nations."

Plagium, in law. See Kidnapping.

Plague, Pestilence, or Pestilential Fever. See Plain Medicine, no 325.

The commission at Moscow, having, in the year 1770, invented a fumigation-powder, which, from several lesser experiments, had proved efficacious in preventing the infection of the plague; in order more fully to ascertain its virtue in that respect, it was determined, towards the end of the year, that ten malefactors under sentence of death, should, without undergoing any other precautions than the fumigations, be confined three weeks in a lazarette, be laid upon the beds, and dressed in the cloaths, which had been used by persons sick, dying, and even dead, of the plague in the hospital. The experiment was accordingly tried, and none of the ten malefactors were then infected, or have been since ill. The fumigation-powder is prepared as follows.

Powder of the first strength.] Take leaves of juniper, juniper-berries pounded, ears of wheat, guaiacum-wood pounded, of each five pounds; common saltpetre pounded, eight pounds; sulphur pounded, six pounds; Smyrna tar, or myrrh, two pounds; mix all the above ingredients together, which will produce a pound of the powder of fumigation of the first strength. [N.B. A pound is 40 pounds Russian, which are equal to 35 pounds and a half or 36 pounds English averduoise.]

Powder of the second strength.] Take southernwood cut into small pieces, four pounds; juniper-berries pounded, three pounds; common saltpetre pounded, four pounds; sulphur pounded, two pounds and a half; Smyrna tar, or myrrh, one pound and a half; mix the above together, which will produce half a pound of the powder of fumigation of the second strength.

Odoriferous powder.] Take the root called kalmus cut into small pieces, three pounds; leaves of juniper cut into small pieces, four pounds; frankincense pounded grossly, one pound; storax pounded, and rose-flowers, half a pound; yellow amber pounded, one pound; common saltpetre pounded, one pound and a half; sulphur, a quarter of a pound: mix all the above together, which will produce nine pounds and three quarters of the odoriferous powder.

Remark on the powder of fumigation.] Guaiacum cannot be had, the cones of pines or firs may be used in its stead; likewise the common tar of pines and firs may be used instead of the Smyrna tar or myrrh, and mugwort may supply the place of southernwood.