Edward Delaval

Edward Hussey Delaval (* 1729, † August 14 1814 in Westminster, London ) was an English chemist and experimental physicists.

Life and work

Youth and Education

Edward Delaval came from a family of landed gentry of Northumberland. Unlike his brothers, who were primarily known for their extravagant lifestyle, Edward developed at an early age an interest in science. After completing his Magister in Cambridge, he became a Fellow of Pembroke College there. In 1759, he was - supported by Benjamin Franklin - Member of the Royal Society of London.

Research on electricity and lightning rod

Even before his induction into the Royal Society Delaval had physical experiments carried out for electricity and corresponds in this respect with Benjamin Wilson. Two years later, another report was published in the Philosophical Transactions, the publication organ of the society, under the title An Account of Several Experiments in Electricity ( " report on some experiments in electricity" ) about his research in this area. 1764 reported Delaval in the Philosophical Transactions of the consequences of a lightning strike in the tower of St. Bride 's Church in London's Fleet Street.

During the second visit to England, Benjamin Franklin in the years 1764 to 1775 Delaval and Franklin were appointed together with other members of the Royal Society in a commission to draw up a proposal for securing the London St Paul's Cathedral against lightning. The results were published in 1769 under the title of Commissioners Proposal of a Method for Securing the Cathedral of St. Paul 's from Damage by Lightning ( " Proposed Method, the Saint Paul 's Cathedral against lightning damage to preserve "). Shortly after the report is completed the tower was actually struck by lightning and Delaval put his views on the subject again dar. From this ensued a controversy about whether the ends of lightning conductors should be as sharp or rounded to the greatest effect on achieve. Against the position Franklin himself Delaval called for rounded ends.

Chemical experiments

As a chemist Delaval led 1755 extensive experiments on glass coloring by the admixture of various metals. His published in this context essay was awarded the Gold Medal of the Royal Society. In 1775 he led, this time jointly with Benjamin Wilson, a series of experiments on the luminous properties of phosphorus by.

While DeLaval's attempts to produce artificial jewels are rather less important, he experienced with the 1777 publication of his book were made to experimental inquiry into the cause of the permanent colors of opaque bodies ( " Experimental investigation of the causes of permanent colors of opaque bodies " ) a great success. The work has been translated a year after the first publication in French and another year later into Italian. 1785 appeared a second edition in England, in 1788 a German translation.

DeLaval's interest in glass also had an impact outside the scientific area. He had a large collection of water- tuned glasses to make music and inspired Benjamin Franklin during one of his concerts in 1761, the invention of the glass harmonica.

Academician and last years

In addition to his membership in the Royal Society Delaval was also a member of the Professional Societies Göttingen, Uppsala and Bologna. When he fell to the legacy of the Delaval family after the death of his brother, he preferred to stay in London. For a foundation to the Newcastle Society of Antiquaries, he received an honorary membership, but returned to his death never to his home Northumberland back. On August 14, 1814 Delaval died as the last representative of his family at the age of 85 years.

Writings

Independent writings

• An experimental inquiry into the cause of the permanent colors of opaque bodies, London 1777, 2nd edition Warrington 1785; French-language edition under the title Recherches sur la cause des EXPERIMENTALES chan gemens de couleurs dans les corps opaques et naturellement colorés, ouvrage traduit de l' anglois ... par M. Quatremère Dijonval ..., Paris 1778; Italian-language edition under the title Ricerche sperimentali sopra le cause de ' cambiamenti de' colori nelli corpi opachi, e colorati: con una Prefazione istorica; relativa all parti di Filosofia esaminate in essa, ed all the various Arti, e Manifatture da quella dipendenti, Bologna 1779; German language edition under the title of experiments and observations on the cause of permanent colors opaque body ... Translated from the English; together with a preface by Dr. Lorenz Crell ..., Berlin and Stettin, 1788.

Journal Papers (selection)