Copy letter from Robert William Frederick Harrison to J Herbert Parsons, 54 Queen Anne Street, W 'Soiree. At a recent meeting of the Soiree Exhibits Committee, mention was made of a portable colour vision testing apparatus, which it was thought would be suitable for exhibition at the Soiree on May 7th. Can you say to whom application should be made in the first instance, with regard to this piece if apparatus?' 16 April 1913