We learn from a foreign exchange that a series of experiments were recently made at the "Woolwich dockyard, England, to iest the comparative strength of wire ropes manufactured by Messrs. Bjnks & Stephenson, under a new patent, and those made under an old one. The new ropes were made of the patent wire invented and manufactured by Webster & Horsfall, Birmingham, which is unquestionably the most remarkable yet produced, the weight which a very small sized coil will bear being almost incredible. The breaking strain, under the old patent and under the new, may be best judged by the comparison made. Thus, an inch and a quarter rope, made under the old patent, broke under a weight of 2 tuns 5 cwt., while under the new, to break the same thickness, it required no less than 4 tuns 19 cwt. A weight of 4 tuns 6 cwt. broke a rope of two inches diameter, made under the old patent, while it required 9 tuns 10 cwt. to break one of the same size under the new patent. The British Board of Admiralty ha\ e the matter under consideration, with a view to its application to the rig-gir g of the ships of the royal navy. It may not be generally known, but it is none tbe less a fact, that a portion of several miles' length of the Atlantic cable (where it is supposed the greatest strain will be exerted) is made of this very wire of Webster & Horsfall. The wonderful superiority in point of tenacity of this patent iron wire may be judged from the fact that a single strand of No. 9 (about the thickness of about one eighth of an inch) will bear 3,360 pounds before snapping, whilst the same sized strand, made of the "best charcoal iron" snaps at 1,250 pounds weight. We understand that there is an agent of Messrs. Webster & Horsfall in New York, who is about making an arrangement for the introduction of the wire rope of these manufacturers into this country.