Dated 1835-1869, 1898. From Working papers, experimental notes and correspondence relating to the development of the electric telegraph, [1836-1960].

Bundle of papers entitled 'experimental apparatus-electricity', comprising working notes and correspondence relating mainly to electric telegraph equipment including a letter between James Clerk Maxwell (1831-1879), physicist and  Professor of Natural Philosophy, King's College London, and Charles Wheatstone, concerning the quantity of electricity required to charge a wire, 1862; notes on various pieces of electrical apparatus, principally components in the electric telegraph, including the induction relay, finger input key, circuit breakers, and proposed equipment designed to improve the performance of telegraph printers and reduce the power consumption of the telegraph, with rough sketches and illustrations; inventory of telegraphic accessories; instructions for the construction of a portable meteorology station; correspondence by John Frederick William Herschel (1792-1871), mathematician and astronomer, regarding Kew Observatory and academic vacancies at the University of Melbourne, Australia, 1848-1852, [1848-1862]. Correspondence between Alexander Siemens (1847-1928), electrical engineer, and John Cutler (1839-1925), Professor of English Law and Jurisprudence, King’s College London, on telegraphic cables, 1898.