Baker, Benjamin

SIR BENJAMIN BAKER:

BB born on 31 March 1840 at Keyford, Frome, Somerset, son of Benjamin Baker

and Sarah Hollis. Was educated at Cheltenham Grammar School until he was 16,

when was apprenticed at Neath Abbey ironworks.

In 1860 left Neath and became assistant to William Wilson who designed

Victoria Station in London, and 2 yrs later he joined the staff of engineer

John Fowler and became particularly involved with the construction of the

Metropolian and District lines of the London Underground. This project

involved considerable ingenuity to overcome the many hazards caused by

difficult soils, underground water, and ruins of Roman and other

civilizations. In 1869, as Fowler's chief assistant, BB was responsible for

the construction of the London Underground District Railway from Westminster

to the City, and also served as consultant for the building of other London

underground lines, all bored deep in the London clay.

During the 1870s, there was much interest in extending the Scottish East

Coast Railway from Edinburgh to Dundee, which required the building of

bridges across the Forth and the Tay. Original Tay Bridge, which had been

built by Sir Thomas Bouch of wrought iron lattice girders, collapsed under

an express train during a storm on the night of 28 December 1879. This

structure had been a considerable achievement, and Bouch had built many

successful bridges to similar designs: however, Tay bridge had been built

without sufficient allowance for the force of wind (at inquiry afterwards,

Bouch said had been misled by erroneous information re wind speeds and

pressure by astronomer royal Sir George Biddell Airy, which proved to be the

case) when the train was on the centre span; plus certain elements in its

design were unsuitable, and inadequate supervision had blighted its

construction.

When Tay disaster struck, Bouch had already begun work on a bridge across

the Forth: this immediately cancelled, and inquiry into whether Forth Bridge

possible made by Fowler, BB and others in 1881. Was only with great

reluctance that British govt allowed bridge to be built across the Forth,

but commission for design won by BB and Fowler, with BB in charge. His

design had several features that made a reputation of the disaster unlikely

• in particular, mild steel (considerably stronger than the same weight

wrought iron) had become available through the new Siemens Open-Hearth

process, which meant that structure would be relatively light. (BB v.

knowledgeable about properties and strengths of metals from time at Neath

Abbey ironworks - plus had researched and written series of articles "On the

Strength of Beams, Columns and Arches", 1868). Plus better estimates of the

wind force which structures were required to withstand in storms were

available. Nevertheless, a rail bridge was very difficult undertaking since

the Forth was 6 m (200 ft) deep: a site allowing the use of the little

island of Inchgarvie as a foundation for the central pier was chosen, and

two main spans were then each of 521 m (1,710 ft). A cantilever structure

(BB had written on cantilevers supported by independent girder as best way

of achieving maximum possible span in series of articles entitled "Long Span

Bridges" in 1867 - exactly system adopted for Forth), which supports the

bridge platform by projecting girders, was used since a suspension bridge -

in which the platform hangs from catenaries - was not considered

sufficiently stables in high winds for a railway. (Bouch's original design

wsa for a stiffened suspension bridge, but this was abandoned after Tay

Bridge disaster). Bridge was opened on 4 March 1890 by Edward VII when

Prince of Wales, and has been in service ever since. For this BB was

knighted by Queen Victoria.

Forth Bridge made BB famous, but had many other projects both in Britain and

abroad to his credit. From 1869 he played a prominent part in engineering

development work in Egypt, and during late 1890s implemented William

Willcocks' plans for the Aswan Dam (built 1898-1902) for storage of water

from the Nile, which realized the dream of desert irrigation. A short while

before beginning the Forth Bridge, with John Dixon he designed the large

wrought iron vessel in which Cleopatra's Needle, the obelisk on the Thames

Embankment, was brought to England from Egypt - and though Needle was lost

at sea (1877), it was later found and safely preserved within the hull of

BB's ship, and then he oversaw its re-erection in London. In the U.S. he was

consulted by James B. Eads on the construction of the St. Louis bridge over

the Mississippi River, and when the first Hudson river tunnel appeared about

to fail, BB was called in to design a pneumatic tunneling shield that

allowed work to be completed (1888-91). He also worked on the docks at Hull

and Avonmouth (1902-08), and served on numerous government commissions and

boards and, among other assignments as a consultant.

More railways, 1890s: With J.H. Greathead, BB was joint-engineer for the

Central London (tube) railway, opened in 1890, in construction of which BB

incorporated an ingenious energy conservation measure (suggested by him 25

yrs earlier) in which he dipped the line between stations to reduce the need

both for braking to a halt and for the increase in power required to

accelerate away. After Greathead's death in 1896, BB also acted as joint

engineer with W.R. Galbraith for the Bakerloo line.

He was president of the Institution of Civil Engineers in 1895-96 and was a

vice president of the Royal Society from 1896 (fellow from 1880). He died a

bachelor on 19 May 1907, at Pangbourne, Berkshire, aged 67.