He was also largely engaged on foreign works. Towards the end 

 of 1863 he visited Egypt, at the request of the Viceroy, to report on 

 doubtful points respecting the Suez Canal, and his emphatic recom- 

 mendations led largely to its completion. He executed a great ship 

 canal in Holland, made designs for navigating the First Cataract 

 of the Nile, and had to do with railways and other large works in 

 Russia, India, the Mauritius, and Brazil. 



He was one of the most active members of the Institution of Civil 

 Engineers, and occupied the position o President in the years 1862 

 and 1863. 



Sir John was not merely a railway maker ; he paid much attention 

 to general principles, and some that he strongly advocated may be 

 mentioned. One was the allowance of greater latitude in regard 

 to gradients. The earlier engineers thought that almost any cost 

 should be incurred for the purpose of getting a road as flat as 

 possible ; and for very heavy traffic to be carried very cheaply this is 

 always true. But Sir John urged that in a vast number of cases it 

 was preferable to adopt steeper gradients, and so to save original 

 outlay. He relied on the mechanical skill of engineers to work such 

 gradients effectively and safely, and contended that this principle 

 would lead to a great extension of the system in districts where it 

 would be otherwise impracticable. It is remarkable how his pre- 

 dictions have been verified. In the days of George Stephenson, 1 in 

 264 was thought very steep, and 1 in 100 was said to require 

 stationary engines. Now 1 in 100 is thought nothing of, and 1 in 40 

 or 50 is allowed for important lines, while for mountain districts we 

 find gradients of 1 in 4, or even steeper still. 



Another principle he advocated was that, when the traffic became 

 very large, railways could never be worked to their full advantage 

 unless special lines were allotted to special speeds, thus separating 

 the quick from the heavy traffic. It was a long time before practical 

 railway managers appreciated this idea, but the pressure of increased 

 traffic has lately forced it on them, and it is now being extensively 

 carried out by duplications of many great lines. 



In 1875-76 Sir John filled the honourable office (succeeding Pro- 

 fessor Tyndall) of President of the British Association, and gave his 

 opening address at Bristol on the 25th August, 1875. He began by 

 saying : 



" Past Presidents have already discoursed on many subjects on 

 things organic and inorganic on the mind, and on things, perhaps, 

 beyond the reach of mind ; and I have arrived at the conclusion that 

 humbler themes will not be out of place on this occasion. 



" I propose in this address to say something of a profession to which 

 my lifetime has been devoted a theme which cannot, perhaps, be 

 expected to stand so high in your estimation as in my own, and I 



