Copy letter from Herbert Rix, to Professor George Howard Darwin, Fellow of the Royal Society 'Dear Sir, We will send the "foam" to the Royal Institution for one of their Fridays if you will kindly forward it to us, but the model has not yet arrived. We received your exhibiting card but no parcel. Yours faithfully, Herbert Rix, Asst Sec RS [Assistant Secretary, Royal Society]'. 18 May 1888