Silberrad, Oswald John 1878 - 1960

English; British

(1878-1960), chemist

Oswald John Silberrad, born on the 2nd April 1878 at Buckhurst Hill, Essex, was a British chemist who specialised in explosives, the related field of dye stuffs and metallurgy. He was educated at Dean Close Memorial School, Cheltenham, the Central Technical College, Finsbury, and the University of Würzburg (1898-1900). At the University of Würzburg he studied under professors such as A R Hantzsch and Wilhelm C Roentgen. in c. 1900 Silberrad worked briefly for the Davy Faraday Laboratory at the Royal Institution, London, experimenting on hydrotetrazines and triazoles;

and in c. 1901 - Research Chemist to W.J. Bush & Co., working on essential oils.

In 1902 Silberrad was appointed head of the experimental establishment at Woolwich of the War Office explosives committee, of which Lord Rayleigh was chairman. Most notable among the explosives that he developed was trinitrophenylmethyl nitroamine, which was introduced into service in 1903 as Silberrad's explosive S. 15 and was later known as tetryl. Through its agency he found a means of causing lyddite to detonate effectively in shell, which it had conspicuously failed to do during the South African War. Sir William Crookes, impressed by the work, minuted the War Office emphasizing the need for larger laboratories and additional staff. As a result Silberrad was instructed to design new buildings and to begin metallurgical research. He was appointed superintendent of chemical research and a member of the explosives committee.

In 1906 this committee was disbanded and Silberrad became a consulting research chemist and director of the Silberrad Research Laboratories, first at Buckhurst Hill, then at Loughton. Although primarily a chemist he had picked up a valuable knowledge of metallurgy and in 1908, at the instigation of the director of naval construction, he investigated the cause of a form of erosion in ships' propellers. Silberrad discovered the cause of this erosion and produced a bronze which withstood it and with which propellers were then made throughout the navy.

In 1915 the scientific committees advising the Ministry of Munitions had insisted that lyddite could be made only in earthenware, so that its manufacture from dinitrochlorbenzene via dinitrophenol, requiring a high temperature, was impracticable. Silberrad, who was honorary consultant to the ministry during the war, showed how it could be made safely in iron vessels, and many thousands of tons were made by this method in both world wars. He developed a flashless propellent for use in large howitzers, utilizing his earlier discovery (1902) of the cause of the flash from a gun. He discovered how to make dyestuffs from a special type of carbon and also from the residues of TNT manufacture. Among his many other discoveries was a new chlorinating agent, a method for manufacturing isoprene, the artificial retting of flax, a plastic explosive free from nitroglycerine, and a new method of blasting petroleum wells. He was the author of numerous scientific papers and of a treatise on the chemical stability of nitrocellulose. He was a fearless experimenter, on one occasion making a kilogram of nitrogen iodide, an explosive which when dry detonates on the slightest touch.

He married in 1922, they had one son. Silberrad died at his home, Dryads' Hall, Loughton, Essex, on 17 June 1960