In some short time afterwards the vessel was finished, and Mr. Day still continued eager for the carrying of his plan into execution; he was uneasy at the idea of dropping the scheme and wished for an opportunity to convince Mr. Blake that he could perform what he had undertaken. He wrote from Plymouth that everything was in readiness and should be executed the moment Mr. Blake arrived. Induced by this promise, Mr. Blake set out for Plymouth; upon his arrival a trial was made in Cat-water, where Mr. Day lay, during the flow of tide, six hours, and six more during the tide of ebb; confined all the time in the room appropriated for his use. A day for the final determination was fixed; the vessel was towed to the place agreed upon; Mr. Day provided himself with whatever he thought necessary; he went into the vessel, let the water into her and with great composure retired to the room constructed for him, and shut up the valve. The ship went gradually down in 22 fathoms of water at 2 o'clock on Tuesday, June 28, in the afternoon, being to return at 2 the next morning. He had three buoys or messengers, which he could send to the surface at option, to announce his situation below; but, none appearing, Mr. Blake, who was near at hand in a barge, began to entertain some suspicion. He kept a strict lookout, and at the time appointed, neither the buoys nor the vessel coming up, he applied to the Orpheus frigate, which lay just off the barge, for assistance. The captain with the most ready benevolence supplied them with everything in his power to seek for the ship. Mr. Blake, in this alarming situation was not content with the help of the Orpheus only; he made immediate application to Lord Sandwich (who happened to be at Plymouth) for further relief. His Lordship with great humanity ordered a number of hands from the dock-yard, who went with the utmost alacrity and tried every effort to regain the ship, but unhappily without effect.
Thus ended this unfortunate affair. Mr. Blake had not experience enough to judge of all possible contingencies, and he had now only to lament the credulity with which he listened to a projector, fond of his own scheme but certainly not possessed of skill enough to guard against the variety of accidents to which he was liable. The poor man has unfortunately shortened his days; he was not however tempted or influenced by anybody; he confided in his own judgment, and put his life to the hazard upon his own mistaken notions.
Many and various have been the opinions on this strange, useless, and fatal experiment, though the more reasonable part of mankind seemed to give it up as wholly impracticable. It is well-known, that pent-up air, when overcharged with the vapours emitted out of animal bodies, becomes unfit for respiration; for which reason, those confined in the diving-bell, after continuing some time under water are obliged to come up, and take in fresh air, or by some such means recruit it. That any man should be able after having sunk a vessel to so great a depth, to make that vessel at pressure, so much more specifically lighter than water, as thereby to enable it to force its way to the surface, through the depressure of so great a weight, is a matter not hastily to be credited. Even cork, when sunk to a certain depth will, by the great weight of the fluid upon it, be prevented from rising.
The English of the Annual Register leaves much to be desired in clarity. It makes reasonably clear, however, that the unfortunate Mr. Day's knowledge of submarine conditions was, by no means, equal to Mr. Blake's sporting spirit. Even to-day one hundred feet is an unusual depth of submersion for the largest submarines.
The credit for using a submarine boat for the first time in actual warfare belongs to a Yankee, David Bushnell. He was born in Saybrook, Connecticut, and graduated from Yale with the class of 1775. While still in college he was interested in science and as far as his means and opportunities allowed, he devoted a great deal of his time and energy to experimental work. The problem which attracted his special attention was how to explode powder under water, and before very long he succeeded in solving this to his own satisfaction as well as to that of a number of prominent people amongst whom were the Governor of Connecticut and his Council. Bushnell's experiments, of course, fell in the period during which the Revolutionary War was fought, and when he had completed his invention, there naturally presented itself to him a further problem. How could his device be used for the benefit of his country and against the British ships which were then threatening New York City? As a means to this end, Bushnell planned and built a submarine boat which on account of its shape is usually called the Turtle.
