[93] The viaducts on the Cornwall Railway between Plymouth and Truro are thirty-four in number. Of these there are nineteen which have from six to twenty openings, and are from 80 to 153 feet in height. The aggregate length of these nineteen viaducts is nearly 2¾ miles.
[94] A drawing showing this form of section is appended to the Report of the Commission on the Application of Iron to Railway Structures, 1849.
[95] The remainder of this letter is printed in Chapter XVI. p. [486].
[96] Mr. Brunel was thoroughly conversant with the principles of mathematical analysis, and was able with great readiness to apply it in practice; but at the same time he preferred, when it was possible, to use geometrical methods of solution for engineering problems.
[97] In the note at the end of this chapter mention is made of some experiments made by Mr. Brunel on riveted joints.
[98] See above, p. 185.
[99] A description of this bridge is given in Humber’s Bridge Construction, vol. i. p. 228, and vol. ii. pl. 70, 71, 72; Molinos et Pronnier, Construction des Ponts Métalliques, p. 328, pl. 20, 21, 22.
[100] See Proceedings Inst. C.E., for 1847-8, vol. vii. p. 138.
[101] After some perseverance, Mr. Brunel succeeded in getting these unusually large links, which were 20 feet long, rolled in a single piece without welding on the eyes. He had to go down himself to the manufactory in order to get the men into the way of doing the work.
[102] See note at the end of this chapter for experiments on ropes and chains. The crabs were designed and made specially for this duty. Each had two barrels, grooved to receive the chain, which was passed several times round both barrels, so as to get sufficient grip; and it was in this way possible to wind in with the crabs any length of chain without having to stop to fleet, as would have been the case had a single-barrelled crab been used.