A study of this vessel shows that she must have been a very stable craft and not likely to dive at an excessive angle or to stand on end, as was the tendency of many of the early diving boats. A report signed by Gen. T. W. Sweeny, U. S. A., and Col. John Michal, Col. T. R. Tresilian, and Major R. C. Bocking, engineers, strongly endorsed this vessel. On the strength of the above-mentioned reports and endorsements, the government, through the Navy Department, appointed a commission composed of Commodore C. M. Smith, Commodore Augustus L. Chase, Chief of Bureau of Ordnance, and Edward O. Mathews, Chief of the Torpedo Board, "to examine, inspect, and report on the merit of said boat." As the report of this commission confirmed the capacity and efficiency of the boat for submarine purposes, the government made a contract for her purchase for the sum of $50,000 (£10,250). The contract specified certain conditions which were to be fulfilled before the final payment was made, one of which was that Halstead should "write out fully and describe, without reservation, all the inventions, secrets, and contrivances necessary to enable any competent person or persons to operate and manage said boat as contemplated, desired, or designed, more especially the methods of furnishing, managing, controlling, purifying, and renewing the air when and in quantity as needed, so as to enable those in the boat to descend and ascend or remain under water any reasonable length of time; also, to open the doors in the bottom of the boat and keep the water from coming therein at any reasonable and regulated depth." For this information Halstead was to receive such further sum as a board of officers might grant. Halstead was to have the further right to apply to Congress for additional compensation. In carrying out the provisions of the contract, the government, on May 27, 1870, took over the _Intelligent Whale_ and then paid $12,050 (£2,470) on account of the contract. Shortly after this Halstead was instantly killed. Differences then arose between Halstead's heirs and others who claimed an interest in the contract. It does not appear that anything further was ever done with the boat to carry out the terms of the contract. She lay neglected for years on the old "Cob dock" in the Brooklyn Navy Yard, but was recently erected as an exhibit on the Green. Some years later that famous inventor, Mr. J. P. Holland, brought out a submarine vessel called the _Fenian Ram_. This vessel was about thirty feet long and six feet in diameter. She was navigated, when submerged, by the use of vertical and horizontal rudders located at the stern. The novel feature introduced in the vessel was an under-water air-gun which was designed to fire a shell under water.