TS copy of letter to the Secretary of the Post Office from W H Preece, entitled 'Marconi's Telegraph.' With MS note [by Baker], 'J C Lamb asked for this report on 12 July.' Describes Preece's own problematic experiments in signalling without wires, and gives the results of experiments using Marconi's patented equipment. Gives the advantages of the system, including its possible use for signalling to remote lighthouses. Preece explains that Marconi has been approached by people wishing to buy the rights to his invention, but has been advised not to negotiate before a decision has been reached by the Post Office, the Admiralty and the War Department, who are all testing Marconi's apparatus. Preece suggests that they offer Marconi £10 000 for his invention. He mentions that Professor Lodge may contest the patent, but he judges Lodge's claim to be unjustified.