15 
gallons, this scheme being from three to five times as costly as Mr. 
W. Webster’s. 
Time warns me that I must not trespass much longer on your atten- 
tion, but before concluding, I should like briefly to mention one of 
the greatest engineering works of modern times, namely the Forth 
Bridge, which has been in progress for the last seven years, and 
which is now virtually complete. The sea, which is here over a 
mile in width, has been bridyed over—the actual length of the 
bridge being 8,296 feet, or nearly a mile and five eighths. It com- 
prises 15 girders of 168 feet each in length, which are simply the 
approaches to the main viaduct, which crosses the intervening 
space of nearly a mile by four spans, namely two of 1710 feet each 
and two of 680 feet each. The largest span of any bridge in this 
country, viz., the Britannia, is little more than a quarter the length 
of the vast spans of the new Forth Bridge. The towers on which 
the shore ends of the spans rest are themselves a stupendous 
engineering work, meaning 360 feet high—than which, only the 
Hiffel Tower, Cologne Cathedral, and the great Pyramid are higher 
structured works. The tensible strength of this bridge is estimated 
at from 30 to 37 tons to the square inch, whilst the utmost strain 
likely to be put upon it, either by wind or weight, is barely one- 
. fifth of that amount. The bridge has been most satisfactorily 
tested by massing upon the two main spans fifty loaded coal 
waggons and three of the heaviest engines and tenders, the total 
weight being over 1,800 tons, more than double the bridge will 
ever be called upon in future to bear. The deflections were in 
exact accordance with the calculations of the joint engineers, Sir 
John Fowler and Mr. Baker. 
Some idea of the vastness of this triumph of engineeing skill 
may be gathered from the following statistics. The foundations 
and piers contain about 130,009 cubic of granite, concrete, and 
rubble masonry, while the bridge itself consists of 53,000 tons of 
steel. Hight million rivets hold the fabric together—the surface 
to be painted is equal to twenty acres. Between three and four 
thousand men have been employed on this gigantic task for the 
last seven years, and the total cost will be two and a-half million 
sterling, which sum is to be defrayed by four railway companies, 
who are uniting in this enterprise for their mutual convenience. 
The successful acchievement of this grand work inspires us with 
confidence for the future. The scheme of a bridge across the 
channel is now occupying many minds, and in the light of what 
has just been done, it seems presumptuous to affirm that such a 
thing is impossible. Time alone can settle this vexed question—it 
may be that ere many years are passed, the scheme of to-day will 
have become an accomplished fact, and we shall then perhaps, 
