If all goes well we shall all gain credit, but ‘_quod scriptum est manet_,’ if the result disappoint anybody, my written report will be remembered by everybody, and I shall have to bear the storm--and all that spite and revenge can do at the Admiralty will be done! The words ‘better sailing qualities than could be given to the “Polyphemus,”’ which I used in my first report to the Admiralty, I believe have never been forgotten. Well, the result of all my anxious thoughts--for I assure you I feel more anxious about this than about most things I have had to do with--is first that we must adopt as _a principle not to be departed from_, that all mechanical difficulties of construction must give way, must in fact be lost sight of in determining the most perfect form--if we find that the screw determined upon _cannot_ be made (but what cannot be done?), then it is quite time enough to try another form; though even then _my_ rule would be to try _again_ at making it.... The ‘Great Britain’ was built wider than the locks through which she would have to pass, as it was supposed that the Dock Company would allow them to be temporarily widened.[132] After a good deal of discussion, negotiations were satisfactorily concluded, and the requisite alterations were made: the ship passed through into Cumberland Basin, and the upper lock was restored to its original state in a few days. On December 10, everything was ready for her passing into the Avon through the lower lock. A steam-tug commenced towing her at high water, but, before she had moved half her length in the lock, it became evident to Captain Claxton, who was on board the tug, that there was not an inch to spare; she was touching the lock walls on either side--in fact, she had stuck between the copings. Upon this he gave orders to haul her back again as quickly as possible. This was hardly effected before the tide began to fall; a few minutes later, and the ship would have remained jammed in the entrance. As the tides had passed their highest, it was necessary immediately to widen the lock, in order not to lose the spring tide; and this was accomplished under Mr. Brunel’s superintendence, just in time to get the vessel through that night. Mr. Brunel described this occurrence in the following letter, written to excuse himself from keeping an important engagement in Wales:-- December 11, 1844.