8 Proceedings of Royal Society of Edinburgh. [sess. 
Hawksliaw, he carried out the extensive works of the Lancashire 
and Yorkshire Railway system. In 1850 he was engaged on the 
construction of the Londonderry and Coleraine Railway, and two 
years later undertook the difficult works of the Ulverston and 
Lancaster Railway across Morecainhe Bay. From that time onward 
his principal works at home included the Solway Junction Railway, 
with its viaduct a mile and a quarter long across the Solway Firth j 
the Clifton Extension Railway ; the Mersey Tunnel Railway ; and 
the Avonmouth, King’s Lynn, and Whitehaven Docks. Abroad he 
constructed the Central Uruguay and Bolivar Railway, the Minas 
and Rio Railway, and the Porto Allegre Railway, and received from 
the Emperor of Brazil the decoration of the Rose. He was one of 
the past Presidents of the Institution of Civil Engineers. He was 
elected a Fellow of this Society in 1878, and died on 2nd June 1892. 
Professor William Dittmar was born in Umstadt, near 
Darmstadt, Germany, in 1833. He entered in 1857 the laboratory 
of Bunsen, and became the assistant of that celebrated chemist. 
Whilst holding this appointment, Professor Roscoe, who had made 
his acquaintance, invited him to become his private assistant. After 
Sir Henry Roscoe’s appointment to the Chair of Chemistry in O wens 
College, Mr Dittmar accompanied him thither, and only left Man- 
chester to become, in 1861, Dr Lyon Playfair’s chief laboratory 
assistant. In 1869 he returned to Germany, and during the next 
three years he acted as a “ Privat Docent ” and Lecturer at Poppels- 
dorff. He returned to Scotland in 1872 to hold under Professor 
Crum Brown the same post which he had held under Sir Lyon 
Playfair. On being offered the newly-instituted Chair of Practical 
Chemistry in Owens College, he removed to Manchester, but 
returned to Scotland on being appointed to the Chair of Chemistry 
in Anderson’s College, Glasgow. 
Critics are united in recognising the thoroughness, great variety, 
and true scientific worth of all he has done. He was awarded the 
Graham Medal for his difficult and successful investigation of the 
“Gravimetric Composition of Water.” He is best known by his 
contribution to the publications of the “ Challenger” Expedition. To 
this work he devoted three years of incessant work. He also wrote 
numerous and voluminous articles for the cyclopedias of Britain 
and the Continent. 
