An impressive and rare Benjamin Martin tellarium / planetarium,

English, circa 1765-70,

Footnotes

Benjamin Martin (bap. 1705, d. 1782) distinguished in the history of scientific instruments and optics, for his contributions to not only the production and sale of scientific instruments, but also through popularising such skills and knowledge through his numerous published texts as well as a dedicated career in lecturing.

A successful businessman of his time, he controversially used hard marketing and repeated advertising of his products, a tactic uncommon and regarded as suspicious by his contemporaries, although latterly becoming common practice.

Martin's broad education led him to open a school in Chichester in his late twenties, which is where he began to start writing the first of many publications. His first text, published in 1735, 'The Philosophical Grammar', focusing on natural philosophy, was inexpensive and accessible to the common person. Over the following five years he continued to lecture and write extensively, leading to a volume published in 1740 on the topic of Optics. This theme sparked great interest in Martin, creating a portable compound microscope with a micrometer a couple of years previously. Instruments of this formation were reproduced into the Victorian era.

At this stage, however, Martin's instruments made of wood and cardboard were crude in comparison to those being manufactured in London at the time. He continued to lecture and write across the country, in Berkshire, Bristol and Bath.

In 1746 and throughout the following decade, Martin travelled across the Midlands and southern England. Whilst continuing his lectures on experimental philosophy, he branched out his writings into the field of linguistics, publishing 'Lingua Britannica reformata' or 'A New English Dictionary' in 1749.

Although orreries were already on the market at this time with other instrument makers, they were expensive and hence their uses not accessible to the majority. Martin wrote in the 1740's that he wished for a planetarium that any gentleman could have made inexpensively. It wasn't until 1756 that Martin settled in Fleet Street, London, where he began to trade as an optician and instrument maker. Short lists of his products for sale at this time indicate he had begun to sell his own orreries. A particular model of Martin's was the basic 'double cone planetarium', which could have attachments such as 'the lunarium', where Earth and Moon balls could be added, and 'the telluriam' arm, which indicated the Earth's annual and diurnal motions.

As a result of his own need for spectacles in his later years, it was a natural progression for Martin to further develop optical instruments, including his invention 'Visual Glasses', which became his shop sign. The apertures were partly covered with an annulus of horn, with green or violet tinted glass lenses.

After obtaining the globe plates and tools of the late John Senex FRS, the following year, Martin expanded into the retail and wholesale of globes. Following a fire at Harvard College, Massachusetts, Martin received commissions for two orreries, a planetarium with tellurian and lunarium attachments and a grand orrery, to replace their collection of scientific instruments in 1764.

Sadly, he was declared bankrupt in 1782, which likely triggered his death the same year. Although his son Joshua Lover Martin had been apprenticed to his father and for a short time from 1778, they had traded as 'Benjamin Martin & Son', he closed the business and all his father's effects were sold at auction.