BABBAGE, Charles (1791-1871). Mathematician and computer pioneer.
Autograph Letter Signed to Sir Henry [perhaps Major General Sir Henry Knights Storks (1811-1874)], 1 page 8vo on black-edged paper with blank leaf, 1 Dorset Street, 8 October 1858. Inviting him and Rawlinson [?the civil engineer Sir Robert Rawlinson (1810-1898)], to come to breakfast.

'Will you breakfast with me on Sunday next at 10 oclock. I have asked Rawlinson and will show you both the means I am organizing for the construction of an Infernal Machine.'

The letter almost certainly relates to Babbage's analytical engine, conceived in the 1830's and worked on sporadically until Babbage's death. This engine was designed to perform all four basic mathematical computations of addition, subtraction, multiplication and division, and to be programmable by punched cards. The engine was to have separate divisions for the actual calculations (the 'mill') and for storing the results, and would be able to take actions based on its own results. It was thus to be far more the predecessor of the modern computer than the earlier 'difference engines', the first of which was only partically constructed and the second only completed by the Science Museum, London, in 1991. Of the analtyical engine DNB records that 'Apart from a few small test assemblies, all that survived in mechanical form is an experimental section of the mill under construction at the time of his death' [Doron Swade in Oxford DNB].
The month 'Sep' has been overwritten with 'Oct' and the day given as 'Friday', which would be correct for October.
[No: 25442]