| Description | Correspondence from W. Groves (Scientific and Telegraph Instrument Manufacturer).
/1 Pencil diagram of rotating mirror instrument, with description beneath, sent from W. Groves to Oliver Lodge (appears to have been enclosed with /3)
/2 Letter from W. Groves to Oliver Lodge, written from 89 Bolsover Street, Portland Place, W, dated 18 November 1889. Groves states that he is sending the rotating mirror and describes some of its workings.
/3 Letter from W. Groves to Oliver Lodge, written from 89 Bolsover Street, Portland Place, W, dated 21 May 1889. Groves explains the delay in sending the rotating mirror and encloses a sketch of the instrument (see /1). |