Thomson's double curb transmitter, probably made by William Thomson (Baron Kelvin), British, 1858.
This instrument was used for transmitting double-current signals through a cable. It was originally designed for use with the 1858 transatlantic cable, but was not completed before the cable failed. It was found that, when sent over a long distance, telegraph signals became weakened and distorted owing partly to the 'capacitance effect' of the mass of seawater. In order to improve the clarity of the signals being transmitted, Thompson designed this instrument to send a second electrical pulse in the opposite direction immediately after the first signal pulse, in order to cut it short and improve precision. The use of this instrument enabled the speed of transmission to be increased from one word a minute to up to 15 words.
- Object Number:
- telegraph peripheral
- component - object
- telegraph instrument
- From Sir William Thomson (Lord Kelvin)
Cite this page
We encourage the use and reuse of our collection data.
Data in the title, made, maker and details fields are released under Creative Commons Zero
Descriptions and all other text content are licensed under a Creative Commons Attribution 4.0 licence
Download catalogue entry as json
View manifest in IIIF viewer
Download manifest IIIF
Our records are constantly being enhanced and improved, but please note that we cannot guarantee the accuracy of any information shown on this website.