Some are initialled by Henry Jameson-Davis. The drawings comprise eleven plans and sections of various components of Marconi's wireless equipment, and were probably preparatory to the construction of the instruments shown. Seven drawings are of oscillators (the key component of Marconi's wireless transmitter) or parts thereof, in perhaps two or three alternative arrangements. One shows a plan view of the coherer receiver, the earliest form of wireless receiver used by Marconi. Two more depict designs for boxes and drawers to house the equipment; a final drawing is unidentified but may be a design for part of the coherer receiver.