As the Marquis wrote the Century in 1655, only seven years after Wilkins’ publication, it is not at all unlikely that he seriously contemplated the contriving of a most useful warlike implement; and this appears the more reasonable when we find the worthy and learned prelate advancing, as it appeared to him, cogent reasons in his 19th chapter, in favour of the “Military offensive engines used amongst the ancients,” as compared to cannon; gravely summing up his observations with the remark--“that the force of these Engines does rather exceed than come short of our gun-powder inventions.” Then again on the ground of expense he shows an advantage in favour of Ballistæ and Catapultæ. Thus: “the price of these gun-powder instruments is extremely expensive.” This is proved from “a whole Cannon weighing commonly 8,000 pounds, a half Cannon 5,000, a Culverin 4,500, a Demi-culverin 3,000,” which “must needs be very costly,” amounting “to several hundred pounds,” for which sum “at least 10 of the ancient timber made engines might be purchased”! Then their transport was a serious matter, for “a whole Cannon does require at the least 90 men, or 16 horses,” and so in proportion for others. But the timber made engines are light, and their “materials to be found everywhere.” Then the gun-powder is costly; “a whole Cannon requiring for every charge 40 pound of powder, and a bullet of 64 pounds,” and in proportion for lesser cannon; whereas those other engines may be charged only with stones. So that only for the superior force of cannon “those ancient inventions” he conceives to be “much more commodious than these later inventions.” Among questions propounded and agreed upon, in January, 1660, to be sent to Teneriffe by the Lord Brouncker and Mr. Boyle, the fifth was,--“Try the power of a stone bow, or other spring, both above and below (the hill), and note well the difference.”--Weld’s Hist. Royal Society, Vol. i. p. 98. 25. How to make a Weight that cannot take up an hundred pound, and yet shall take up two hundred pound, and[6] at the self-same distance from the Centre; and so proportionally to millions of pounds. Footnote [6] and--omitted.