With the increase in amateur interest in astronomy during the eighteenth century, the demand for telescopes grew. The equatorial telescope, while less accurate than larger quadrants or transit instruments, could be aligned with the polar axis, and enable the rising class of amateur astronomer to follow the motion of a star with a single motion. Due to their versatility and portability they were often referred to as 'portable observatories'. Anita McConnell records Sir Joseph Banks (1743-182), the Earl of Bute John Stuart (1713-92) and his brother Stuart Mackenzie (1719-1800) as early buyers of Ramsden's equatorials; Ramsden's invoice to Banks was for £63. Another equatorial instrument would find its way into the possession of the soon-to-be third president Thomas Jefferson by 1792.
Jesse Ramsden, widely acknowledged as one of the leading instrument makers of the period, invented the celebrated dividing engine, the 'Ramsden eyepiece', and two types of micrometers. Ramsden's skill as an instrument maker and scientific abilities led to his election to the Royal Society in 1786 -- he would then win the Society's Copley Medal in 1795 for 'his various inventions and improvements of philosophical instruments' -- and membership of the Imperial Academy of St Petersburg in 1794. However, the corollary of his outstanding workmanship was an obsessive perfectionism; this trait frequently led to delays, much to the annoyance of his clients. In one instance, it caused a twenty-eight year interval between the commissioning and completion of a 6-feet diameter mural circle for Dunsink observatory in Ireland; in another, 'Ramsden drove down to Kew palace with an instrument which George III had ordered. He asked if the king was at home, and insisted on being admitted. The king received him graciously, and, after examining the instrument, said to him: "I have been told, Mr Ramsden, that you are considered to be the least punctual of any man in England; you have brought home this instrument on the very day that was appointed. You have only mistaken the year"' (ODNB).