Letter and note from James Spratt to Pemberton Gibbs regarding his patented copper lightning conductor.

Benjamin Franklin invented the lightning rod in 1749. In 1860, electrician James Spratt patented his innovative woven copper lightning conductor which represented an advance in safety.

Spratt is perhaps better known as the first manufacturer of dog biscuits. He employed Charles Cruft, who went on to establish Crufts, the world-famous show for dog breeders.

This letter is written on the reverse of promotional literature for Spratt's patent flat woven excitation copper conductors with a note requesting the delivery of the lightning conductor etc... to Messrs. Joseph Hart & Son, Wych Street, Strand. It is signed and dated by Spratt on 11th July 1863.

In the letter, Spratt states that it is 'a great privilege' that 'I should permit my Patent Lightning conductor ... to be transferred to the South Kensington Museum.