“Bulstrode Whitelock, in his ‘_Memorials of the English Affairs_,’ London, 1732, folio, page 263, enables us to add to this account, that on Colonel Rainsborough’s advance to Southwark, he found the Bridge gates shut, the Portcullis lowered, and a guard within; but upon placing a counter-guard with two pieces of ordnance, against the gate, in a short time the great fort was surrendered; about two in the morning of Monday, the 2nd of August, 1647.
“A curious invention, which, very probably, was never carried into execution, was, in the year 1643, connected with the history of London Bridge; being the scheme of an unsuccessful engineer named Captain John Bulmer. You may see an original copy of his ‘_Propositions in the Office of Assurance, London, for the Blowing up of a Boat and a man over London Bridge_,’ in the King’s Collection of Tracts in the British Museum, Miscellaneous Pieces, volume 3*, folio, article 88. In this statement, which consists of a broadside of one page, he thus commences. ‘In the name of God, Amen, John Bulmer, of London, Esquire: Master and Surveiour Generall of the King’s Maiestie’s Mines Royall, and Engines for Water-workes, propoundeth--by God’s assistance,--that he, the said John Bulmer, shall and will, at and in a flowing water, set out a Boat or Vessell with an Engine, floating with a man or a boy in and aboard the said Boat, in the River of Thames, over against the Tower-wharfe, or lower. Which said Boat, with the said man or boy in or aboard her, shall the same tide, before low-water againe, by art of the said John Bulmer, and helpe of the said engine, be advanced and elevated so high, as that the same shall passe and be delivered over London Bridge, together with the said man or boy in and aboard her, and floate againe in the said River of Thames, on the other side of the said Bridge, in safety.’ He then proceeds to covenant for himself, his heirs, &c., to perform this within the space of one month, after he shall have intimated at the Assurance Office that he is about to put it in practice. This announcement was to be made ‘so soone as the undertakers wagering against him six for one,’ should have deposited in the Office such a sum as he should consider sufficient to ‘countervaile his charges of contriving the said Boat and Engine.’ Captain Bulmer was also to deposit his proportion of the money, and the whole, being subscribed and signed, was to remain in the office, until he had either performed his contract, when he was to receive it; or till his failure, when it was to be re-delivered to the subscribers. This curious paper is dated November the 6th, and concludes with the following promise: ‘And all those that will bring in their monies into the Office, shall be there assured of their losse or gaine, according to the conditions above mentioned.’ I imagine, however, that this scheme met with but little or no encouragement, because I find a new edition of it, dated March the 20th, 1647, printed in small folio, and inserted in the King’s Tracts marked ‘_Single Sheets_,’ volume 5, article 130. It varies, however, somewhat from the foregoing, and states that ‘the blowing up of a Gun from under the water by the breath of a man’s mouth, shall occasion the raising of such Boate or vessell; which said gun shall then forthwith after be discharged by fire given thereunto, and presently sinke againe: after the sinking whereof, another gunne shall be raised by such meanes as aforesaid, which shall be discharged also, forthwith upon the floating of the said Boate or Vessell on the other side of the sayd Bridge.’ He no longer mentions his terms to be ‘six for one,’ but states that his performance shall take place within a month after the amount of his expenses shall be subscribed by ‘persons pleasing to afford assistance and furtherance to arts and mysteries of this nature.’ He adds too, that security will be given at the office, and that his reason for desiring these deposits is, ‘for that losse of time in collection of the same after performance, would hinder him from prosecution of businesse of greater consequence, and tending to the publique good.