Abraham Fletcher (1714 – 1 January 1793) was an English mathematician.
Fletcher was born in Little Broughton, Bridekirk, Cumberland, was the son of a tobacco-pipe maker, who taught him his own trade, but gave him no higher instruction. The boy learnt to read, write, and cipher as he best could, applying himself particularly to the study of arithmetic, from which he proceeded to the investigation of mathematical theorems. After the day's toil in the workshop he would hoist himself by a rope into the loft over his father's cottage, in order to pursue his studies uninterruptedly. Having worked through Euclid he set up as a schoolmaster at the age of thirty, and acquired considerable reputation as a teacher of mathematics.
He married early. His wife, like his parents, discouraged the pursuit of learning as an unprofitable thing. Turning his attention to botany, Fletcher studied the properties rather than the classification of plants; increased his income by the sale of herbal decoctions, and was known to his neighbours as ‘Doctor Fletcher.’ He also studied judicial astrology, and cast his own nativity, which Hutchinson found in one of his books. ‘This gives,’ says another astrologer, ‘seventy-eight years and fifty-five days’ duration of life. Fletcher lived seventy-eight years seventy-one days, dying on 1 January 1793.
- The Universal Measurer; the Theory of Measuring in all its various uses, whether artificers' works, gauging, surveying, or mining, Whitehaven, 1753, 2 vols. 8vo.
- The Universal Measurer and Mechanic, a work equally useful to the Gentleman, Tradesman, and Mechanic, with copperplates, London, 1762, 8vo.