_Secondly_—“’Tis safe from the Uncertainty of Tides and the Violence of Tempests, which do never move the Sea above Five or Six paces deep, from Pirates and Robbers which do so infest other Voyages. From Ice and great Frosts, which do so much endanger the Passages towards the Poles.” Could Bishop Wilkins but have perused Mr. John Holland’s article in the _North American Review_ for December, 1900, in which proposals for a submarine passenger service across the Channel are put forward, he would have been gratified to find the inventor of a practical under-water vessel of the same opinion as himself regarding the “advantages and conveniences” of travelling beneath rather than on the waves. M. Goubet also has imagined a submarine cross-Channel service. _Thirdly_—“It may be of very great advantage against a Navy of Enemies, who by this means may be undermined in the Water and blown up.” Sixty-seven years after these words were written David Bushnell launched his submarine boat, which carried a torpedo charged with 130 lbs. of gunpowder to be affixed to the side of the vessel to be blown up. In 1864 the _David_, owned by the Confederates, blew up the _Housatonic_, and though this is the only occasion on which a submarine has done any damage to the foe in an actual real encounter, it is more than likely that in the next great naval war under-water vessels may “be of very great advantage against a Navy of Enemies.” _Fourthly_—“It may be of special use for the Relief of any Place that is besieged by Water to convey unto them Invisible Supplies; and so likewise for the Surprizal of any Place that is accessible by Water.” _Fifthly_—“It may be of unspeakable Benefit for Submarine Experiments and Discoveries, as—The several Proportions of Swiftness betwixt the ascent of a Bladder, Cork, or any other light Substance, in comparison to the descent of Stones or Lead. The deep Caverns and Subterranean Passages where the Sea Water in the course of its circulation, doth vest itself into other Places and the like. The Nature and Kinds of Fishes, the several Arts of Catching them, by alluring them with Lights, by placing divers nets about the sides of this Vessel, shooting the greater sort of them with Guns, which might be put out of the ship by the help of such Bags as were mentioned before, with divers the like Artifices and Treacheries, which may be more successfully practised by such who live so familiarly together. These fish may serve not only for food but for Fewel likewise, in respect of that oil which may be extracted from them; the Way of Dressing Meat by Lamps being in many Respects the most convenient for such a Voyage. The many fresh springs that may probably be met with at the Bottom of the Sea, will serve for the Supply of Drink and other Occasions.”