adapt the exterior to our use, I drew a plan for the interior, with the apartments necessary for legislative, executive, and judiciary purposes; and accommodated in their size and distribution to the form and dimensions of the building. These were forwarded to the Directors, in 1786, and were carried into execution, with some variations, not for the better, the most important of which, however, admit of future correction. With respect to the plan of a Prison, requested at the same time, I had heard of a benevolent society, in England, which had been indulged by the government, in an experiment of the effect of labor, in _solitary confinement_, on some of their criminals; which experiment had succeeded beyond expectation. The same idea had been suggested in France, and an Architect of Lyons had proposed a plan of a well-contrived edifice, on the principle of solitary confinement. I procured a copy, and as it was too large for our purposes, I drew one on a scale less extensive, but susceptible of additions as they should be wanting. This I sent to the Directors, instead of a plan of a common prison, in the hope that it would suggest the idea of labor in solitary confinement, instead of that on the public works, which we had adopted in our Revised Code. Its principle, accordingly, but not its exact form, was adopted by Latrobe in carrying the plan into execution, by the erection of what is now called the Penitentiary, built under his direction. In the meanwhile, the public opinion was ripening, by time, by reflection, and by the example of Pennsylvania, where labor on the highways had been tried, without approbation, from 1786 to '89, and had been followed by their Penitentiary system on the principle of confinement and labor, which was proceeding auspiciously. In 1796, our legislature resumed the subject, and passed the law for amending the Penal laws of the commonwealth. They adopted solitary, instead of public, labor, established a gradation in the duration of the confinement, approximated the style of the law more to the modern usage, and, instead of the settled distinctions of murder and manslaughter, preserved in my bill, they introduced the new terms of murder in the first and second degree. Whether these have produced more or fewer questions of definition, I am not sufficiently informed of our judiciary transactions to say. I will here, however, insert the text of my bill, with the notes I made in the course of my researches into the subject.[15]