[1] As consulting engineer Farey worked for many well-known inventors of the later Industrial Revolution, and was a witness to a number of parliamentary enquiries, inquests and court cases, and on occasion acted as an arbitrator.

[2] From 1791 to 1802, he lived in Woburn, Bedfordshire, where his father was stationed as surveyor and land agent for Francis Russell, 5th Duke of Bedford.

[1] At the age of fourteen Farey was commenced to make drawings for the illustrative plates of Rees's Cyclopædia and the 'Edinburgh' encyclopedias, 'Tilloch's Magazine,' Gregory's 'Mechanics' and 'Mechanical Dictionary,' the 'Pantalogia,' and many other scientific works.

Farey accepted an appointment at the lace manufactory of John Heathcoat in Devonshire,[1] which, however, he gave up in 1823, In 1825, took the engineering direction of Messrs. Marshall's flax-mills at Leeds; this position he was obliged to relinquish in 1826 in consequence of the failure of his brother's health and the necessity for his return to London, where he resumed his profession of consulting engineer, and from that time was engaged in most of the novel inventions, important trials in litigated patent cases, and scientific investigations of the period.

[3] Farey joined the Institution of Civil Engineers as a member in 1826, served several offices in the council, and always took great interest in its welfare.

His residence, 67 Great Guilford Street, Russell Square, London, was burnt down in 1850, when considerable portions of his library and documents were injured or destroyed.

[3] His health, which had been failing since the death of his wife, now received an additional shock, and he died of disease of the heart at the Common, Sevenoaks, Kent, on 17 July 1851.

[4][3] In an accompanying letter printed in the Transactions, Farey explained in general: WITH this you will receive an instrument of my invention for drawing lines converging to a distant point.

I shall be obliged to you to communicate this to the Society.The first instrument of this kind, I made in the year 1807, and I have had it in constant use ever since, as it applies with advantage to almost every perspective drawing; l have been induced to present it to the Society, at the request of several members...[4]An additional four page long explanation of Farey's "Instrument for drawing Lines to an inaccessible center" in Plate 2 (see image fig.

in perspective, as the points to which the lines for such drawings should converge, will often fall at a distance of I2 and 15 feet from the picture, so as to render it impracticable to employ rulers of sufficient length to reach the points, and there is, except this instrument and Mr. Nicholson’s lately invented, no other practicable method of drawing such lines.The instrument consists of three rulers, A B and D, figs 4, which are united by a common centre-screw a, and have a thumb screw d, which fixes them fast at any angle at which they may be placed...etc, etc.

The device became so popular, that the 6th edition of the Encyclopædia Britannica (1824) included an article about it, which started with: ELLIPTOGRAPH, an instrument for drawing ellipses.