ParaLock Plotter-Britains National Maritime Museum

Weems Paralock Plotter to be included in Britain’s National Maritime Museum Collection in Greenwich

Weems & Plath is pleased to announce that in response to the request of Britain’s National Maritime Museum in Greenwich, England, a ParaLock Plotter (#90) was donated to their collection on February 25, 2015. The museum has collected over three thousand navigation and astronomical instruments and 57 parallel rules. The oldest of these dates back to around 1750. Many of these rules are made of ivory, ebony, silver or brass.

It is believed that this is the first time that the museum has acquired an instrument from its living inventor! The accompanying photograph shows the inventor, David Young, outside the Museum. The occasion was particularly timely as sales of the ParaLock Plotter are approaching 10,000 units. The Paralock Plotter was patented in 2006 and first made available to the public in the summer of 2007.

According to President of Weems & Plath, Peter Trogdon, "The success of the Paralock Plotter is due to the special features it offers the user which are not available with other parallel rules. It has been over 200 years since any significant improvements have been made to the parallel rule."

Navigation and Astronomical Instruments
Navigation and Astronomical Instruments

The particular inventive step of the ParaLock Plotter is the patented ‘locking knob’ which enables the rule to plot or derive latitude and longitude positions onto or from a paper chart. Secondary advantages are the suitability for small chart tables and the patented ‘finger holes’ which improve speed and feedback during the plotting process.

For more information about the Weems Paralock Plotter(#90), please contact Weems & Plath.



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