Iron, as a Material for Ship-Building; Being a Communication to the Polytechnic Society of Liverpool Paperback - 2012

From the publisher

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1842 Excerpt: ...years since on an iron steamer called the " Alice," built for the trustees of the Duke of Bridgewater's canal. As iron vessels are generally built, it is very difficult to make correct observations to ascertain the effect of rivetting. This operation proceeds at short intervals, and in different parts, as the plates are applied; and it would be almost impossible, should any alteration be observed in the compass, to ascertain whether it was caused by the plating or by the rivetting. Not having any premises near the water, where the " Alice" was built, we first erected her at our boiler yard, and afterwards re-erected her on a vacant piece of land at the water's edge, from which she could be launched in the usual way. It appeared to me that this presented an opportunity to ascertain the effect produced on a vessel by rivetting. When, therefore, the plates had been put together at the water's edge, and before the rivetting was commenced, I obtained a very delicate needle, and made a few accurate observations as follows: --I drew a long line a-head of the vessel in the direction of the keel; and having selected a point at a considerable distance, where I could perceive no effect on the compass, I ascertained the direction in Avhich the vessel pointed. I then measured 100 yards from the vessels stem, and there fixed the compass on the plane of the lower side of the keel. I could not here perceive any deviation, but, as I moved forwards towards the vessel, the disturb ance became very considerable. I carefully noted down all these results, and also made an observation under each quarter of the vessel. I now waited till the vessel was entirely rivetted and nearly ready for launching, and then fixed the compass in the same places as before, and a...