Patent Compensating Portable Barometer by William Harris London

A patent compensating portable barometer by William Harris & Son, London.

This example is comprised of a thirteen inch rosewood case containing a silvered scale plate with thermometer, glass cistern and setting dial for recording the day’s reading which is hand operated from the underside of the case. The right hand side of the case has a sprung brass knurled knob to allow for the accompanying silvered scale to be slid up and down to record the temperature and provide the associated reading from the level in the cistern.

The top of the scale is engraved to “William Harris & Son, 50 High Holborn, London” and vertically engraved to the right hand side of the thermometer with, “Harris’s Patent Compensating Portable Barometer”.

William Harris was the son of the London optician Richard Harris but was apprenticed in 1788 to a Joseph Robinson who is described as a motion maker. With a seven year apprenticeship it is likely that Harris would have earnt his freedom by 1795 although he does not appear in the records until 1800 where he is listed as trading from his premises at 50 High Holborn.

His capabilities must have brought him early success, by 1809 it is known that Sir David Brewster had commissioned Harris to construct a goniometer after his designs. Brewster relates that,

“On the 3^rd of February 1809, I gave direction to Mr Harris to construct for me a goniometer for measuring by reflection the angle which one line forms with another, or the angle formed by two reflecting surfaces, by observing their relative position to any straight line. I shewed this goniometer to several of my friends in London, during the months of February and March; to Dr Clarke and Mr Woodhouse at Cambridge, on the 22^nd of March; and , in the beginning of April, it was exhibited to the mathematical class of this University by Professor Leslie. At this time I got an addition made to the instrument by Mr Adie”.

The relationship evidently flourished as two years later on the 21^st of May 1811, a patent for, “Optical instruments for measuring angles; telescopes and other instruments” was lodged at the Patent Office by both Brewster and William Harris. That Brewster shared the patent with Harris is proof of the latter’s growing wealth as it would have consumed significant cost and time to complete the process. Brewster was never a man of great financial means according to his biographers and that William Harris was responsible for the administration is clearly stated in the patent itself. “And be it remembered that on the thirteenth day of July, in this year of our Lord 1811, the aforesaid William Harris came before our said Lord the King in his Chancery, and acknowledged the specification aforesaid”.

It is unlikely given the existing rarity of the instruments from this long patent application that many were produced and his early foray into commercialising his inventions was largely overshadowed in 1817 when Brewster’s invention of the kaleidoscope was revealed.

That Harris seems not to have been involved in either the patent application for the kaleidoscope or advertised as one of the licensed retailers alongside such famous cotemporaries as the Dollonds. Robert Brettell Bate, Matthew Berge and Thomas Jones (amongst others) suggests that their relationship had run its course. Brewster was known to have been a somewhat difficult character so we may assume that the relationship has broken down by then. It is also asserted that Harris by his exclusion from the above list may have been the responsible party for having shown the invention to other scientific manufacturers at the early stages of the instruments conception, examples of kaleidoscopes by Harris certainly exist. Brewster by virtue of its immediate popularity fell prey to numerous imitators and although he held rights under patent law, seemed never (probably for lack of funds) to have tested his rights under law.

Rumours of Harris’s inattention to secrecy seem not to have affected his business, he is listed as having satellite premises in both Liverpool and Hamburg by 1820, at which point the business name was adjusted to William Harris & Co and he supplied instruments to the JA Lloyd survey of Panama during the 1820’s. Under this new title, his son Richard Joshua Harris would also have started his apprenticeship and latterly introduced to his Father’s business, the firm however did not change to William Harris & Son until 1840 after the satellite businesses and associated partnerships were dissolved.

Harris’s trade cards of the period are often marked with the words, “by his Majesty’s Royal Letters Patent” which was almost certainly a useful hangover from his earlier partnership with Sir David Brewster. The telescope for which he received this accolade was the only patent that Harris ever applied for which is interesting given that his new portable compensating barometers were all variously marked with the word “patent”. The process was perhaps less well policed in the Nineteenth Century and Harris was not the only maker to take advantage or exaggerate his entitlement but it does suggest something about his character that he would not only re-create the sympiesometer that was invented by another famous Brewster associate, Alexander Adie. Furthermore, he also falsely publicised a patent for a similarly functioning instrument. Nevertheless, his actions seemed to have gone unnoticed as William Harris & Son continued to advertise this instrument throughout the 1840’s and it is listed in 1851 amongst the Great Exhibition’s catalogues as a showcase product of the company’s stand. It is interesting to note that Brewster was also an exhibitor and juror at The Great Exhibition.

An advertisement in the 1847 Magazine of Science below provides Harris’s detailed explanation of the instrument in question.

Circa 1845