c PRISM PRISONS AND PRISON DISCIPLINE was obtained by bribing some of the court officials. Another synod, held at the instance of Bishop Ithacius at Bordeaux in 384, when Maximus had usurped the throne, again gave an adverse decision. Priscillian appealed be- fore the emperor, who sentenced him to death and decreed the confiscation of his proper- ty. Priscillian's execution is the first instance of a Christian condemned to death for heresy. The doctrines held by the Priscillianists were a mixture of Manichseism and Gnosticism. PRISM, in geometry, a solid bounded by plane faces, of which two that are opposite are equal, similar, and parallel, and are called the bases of the prism ; the other surfaces are parallel- ograms. The axis is the line connecting the centres of the bases. The prism is triangular, square, pentagonal, and so on, according as the figure of the bases is triangular, square, pen- tagonal, &c. It is right or oblique according as the sides are perpendicular or oblique to the bases. A right prism is regular when its bases have the figure of a regular polygon. The prism corresponds among bodies with plane surfaces to the cylinder among bodies with curve surfaces. In optics, a prism is a portion of a refracting medium bounded by two plane surfaces inclined to one another. The line in which these two surfaces meet, or would meet if produced, is the edge of the prism; their inclination is called its refracting angle. The form commonly used is a triangular prism of glass. A good contrivance for delicate experi- ments may be made with two rectangular pieces of plate glass firmly set to form two sides of a triangnlar box which is to be filled with water or spirits of turpentine. The prism is essen- tial in apparatus for decomposing light. PRISONS AND PRISON DISCIPLINE. Peniten- tiary science, or the system of detaining, pun- ishing, and reforming criminals, is of modern origin. The Scriptures contain references to prison houses and to the punishment of offend- ers. In Greece and Rome punishments were inflicted by loss of caste, of citizenship, and of liberty, banishment, and penal labor, which was sometimes performed on public works, in quarries, mines, &c. In the Roman em- pire there were houses, called ergastula, used chiefly for the punishment of criminal and re- fractory slaves. In Rome there still remains a prison, known as the Mamertino caves, con- sisting of several vaults or apartments. (See ROME, vol. xiv., p. 411.) The feudal barons had towers in their castles called donjons, whence is derived dungeon, for the confine- ment of their captive foes or refractory re- tainers. Sometimes the prison vaults were out in the solid rock below the surface of the earth. A movement for the amelioration of the wretched condition of English prisons and prisoners was begun by John Howard, whose investigations led to the enactment of two laws by parliament in 1774, one abolishing prison fees (which up to that time had been exacted from all prisoners) and the protracted confinement of the prisoner until these were paid, the other providing for an improvement of the sanitary condition of jails. In 1777 appeared the first work of Howard on pris- ons, "The State of the Prisons in England and Wales." The works of Beccaria on crime and punishment appeared about the same time on the continent ; and in England Sir William Blackstone, Mr. Bentham, and Mr. Eden en- tered upon the work of prison reform in ear- nest. The prisons were found to be in the most wretched condition, while the treatment to which the prisoners were subjected was de- moralizing in the highest degree. In 1776 a prison was built at Horsham by the duke of Richmond under Howard's advice and coupe-r- ation, and was a marked improvement upon any prison then existing. In 1778 an act for the establishment of penitentiary houses was passed through the efforts of Howard, Eden, and Blackstone. The leading principles of the new system were that " if any offenders con- victed of crimes for which transportation has been usually inflicted were ordered to solitary imprisonment, accompanied by well regulated labor and religious instruction, it might be the means under Providence, not only of deter- ring others, but also of reforming the individu- als and turning them to habits of industry." There was much delay in carrying out the pro- posed reforms. In 1791 Jeremy Bentham published his "Panopticon, or the Inspection House," containing a plan for a model prison; but it was not till 1821 that the great peniten- tiary at Millbank on his model was completed, though it had been opened in 1817. It com- prised six pentagonal structures radiating like the spokes of a wheel from a central hexagon, from which all the cells were visible. This prison was torn down in 1875. In 1842 was opened the cellular prison at Penton ville. Gov- ernment convict prisons have also been estab- lished at Brixton, Portland, Chatham, Ports- mouth, Parkhurst, Dartmoor, and Woking. The convict prison at Fulham is exclusively for fe- males, who are also sent to Woking. Early in the present century Mrs. Elizabeth Fry com- menced her mission to the female prisoners in Newgate ; and in 1818 Mr. (afterward Sir T. F.) Buxton published an " Inquiry whether Crime and Misery are produced or prevented by the present System of Discipline." From this work it appears that, notwithstanding Howard's exposures, Mrs. Fry's revelations, and the developments made by the committee of aldermen of London in 1815, the abuses of Howard's time still continued, and had in many particulars increased, and that a radical and thorough change was needed. The hulks of men-of-war were for a time used as prisons, but have been abandoned. In the United States, the work of reform was begun in Philadelphia in 1776, and has been steadily carried on by a large number of philanthro- pists and publicists. Chief among these have been Louis D wight, Roberts Vaux, one of 'he
