The cost of ironclads to this country has been very serious. Mr. Reed puts it down at a million sterling a year since their inauguration.(46) For the eighteen years preceding 1876, they cost £16,738,935, and with the cost of wear and tear, repair, and maintenance, not less than £18,000,000. £300,000 was required for repairs and maintenance alone in one year, perhaps an exceptional case. The _Warrior_, built in the year 1860, cost, to 1876, for maintenance and repair, no less than £124,245, or about a third of her original cost. She is the earliest type of ironclad, and of small tonnage compared with several of her successors. What _they_ may cost to maintain is a still more serious problem. Single ironclads have cost the country half a million sterling; the _Inflexible_, £600,000. [Illustration: PREPARING FOR TORPEDO EXPERIMENTS AT PORTSMOUTH.] Connected intimately with the ironclad question is the torpedo movement. From an early date schemes have been devised for injuring an enemy’s vessel by submarine apparatus and otherwise than by guns. In the seventeenth century, we find the celebrated Marquis of Worcester describing such apparatus. The ninth of his “Century of Inventions” describes a small engine, portable in one’s pocket, which might be carried and fastened on the inside of the ship, and at any appointed time, days or weeks after, at the will of the operator, it should explode and sink that vessel. In his tenth invention, the Marquis of Worcester describes “a way from a mile off to dive and fasten a like engine to any ship, so as it may punctually work the same effect, either for time or execution.” The details of construction and working are left to the reader’s imagination.