Horace Darwin was the 9th child of Charles and Emma Darwin born in May 1851. He established the Cambridge Scientific Instrument Company with A.G. Dew Smith in 1878 and went on to have exclusive control of it from 1891. The company became affectionately known as ‘Horace Darwin’s shop’ and Horace employed a certain Robert Whipple as his personal assistant. Whipple later became the company’s managing director and then chairman.
We have two items connected to Horace: a reprint of a lecture he delivered in 1913 and a two volume set which belonged to him. “Scientific instruments, their design and use in aeronautics” was given as the first Wilber Wright Memorial Lecture on the 21st May 1913 and printed in the Aeronautical Journal of July 1913. In it Horace discusses scientific instruments used on aeroplanes and the difficultly in designing them due to vibrations of the planes while in the air. He then looks at the basics of instrument design, including geometrical design and how by changing the placement of parts of an instrument it could be improved. Horace does make use of his family connections twice, in the first part he quotes from Erasmus Darwin’s Botanic Garden  and then later he links to his father’s work by stating:
“It is advantageous that ‘the survival of the fittest’ should take place early in the life of the machine, and by this means, in fact, it takes place before the design is complete”
The second item we have relating to Horace is John Morley’s two volume set entitled Diderot and the encyclopædists [London: Chapman and Hall, 1878; STORE 133:23-24]. These books contain Horace Darwin’s book plate and someone has written his name on the fly leaf (see photoe above).
Dawn Moutrey, Library Assistant