When at Blackwell’s Island yesterday afternoon, pursuing our inquiries respecting the Female Penitentiary prisoners, sent there from Bellevue, we considered it appertaining to the duty assigned to us, to extend our inquiry to the occurrences relating to the same subject, which happened on that Island, the institution there being a part of the Bellevue establishment. We were informed by Dr. Spring, the physician stationed there, that the first case of malignant cholera which occurred on the Island, was an Alms-house pauper, who slept there, but worked on the Long Island farms; he was permitted to go as far as Brooklyn, July 1st, but he frolicked in the city all the next day, returned at night to Blackwell’s Island, and slept out of doors all night, and sickened and died July 3d--no other case took place there until the 11th, (three days after the Female Penitentiary prisoners were removed from Bellevue,) when three persons sickened and died the same day; one, a very feeble black man, aged sixty-five; another, a black lad, who had been much reduced by medical treatment for rheumatism--both patients in the hospital, and able to take exercise out of doors. Their building is about one hundred yards from that occupied by the Female Penitentiary prisoners. The third, a white pauper, aged sixty-five, who worked on the Long Island farms, but slept on Blackwell’s Island, formerly in the shanty now occupied by the sick blacks; but some days before he sickened, he slept in a small building at a considerable distance from his former lodging place; but he not being under confinement, would go to any part of the Island when unobserved, and without hindrance to the outside of the Black Hospital.--Since then, three blacks have had that disease. We were also informed by Dr. Spring, that no case of malignant cholera had occurred among the two hundred and eight male Penitentiary prisoners--that a lad, aged sixteen, who frequently complained of being unwell, died on the 13th inst., after three or four hours sickness of common cholera. Those men are employed in the open air, and their prison is in the most perfect order; the air within was as free from any impure smell as the atmosphere without. We were informed by Col. Woodruff, the superintendent, that it was in contemplation to remove the Bridewell prisoners from Bellevue to this prison--and asked our opinion as to the propriety of the measure; we give it as our opinion, that as there was already a large number of men now confined there, and room only for about thirty more, that the crowding of the prison at this time, and especially from places where the malignant cholera existed, would be exposing the health of the prisoners to some hazard.