Details
Wavemeters:
a Marconi wavemeter with Marconi's Wireless Telegraph Co. Ltd. condenser ('06 patent), leather-lined compartment and turned boxwood container, in (defective) teak case; and two Emerald valve wave meters by Heath & Co, No. 2 and No. 23, for 20-60 and 200-600 metres respectively, each with D.E.R. valve in mahogany case, one with instruction leaflet (3)
a Marconi wavemeter with Marconi's Wireless Telegraph Co. Ltd. condenser ('06 patent), leather-lined compartment and turned boxwood container, in (defective) teak case; and two Emerald valve wave meters by Heath & Co, No. 2 and No. 23, for 20-60 and 200-600 metres respectively, each with D.E.R. valve in mahogany case, one with instruction leaflet (3)