Dictionary of National Biography, 1885-1900/Crabtree, William
CRABTREE, WILLIAM (1610–1644?), astronomer, son of John Crabtree, a ‘husbandman’ of fair estate, was born at Broughton, near Manchester, in 1610, and baptised at the collegiate church of Manchester on 29 June that year. He was educated, it is presumed, at the Manchester grammar school, but did not go to Cambridge, as is sometimes stated. In due time he engaged in the business of a clothier or chapman (equivalent to a merchant of to-day), and seems to have been in comfortable circumstances. In his twenty-third year (14 Sept. 1633) he married Elizabeth, daughter of Henry Pendleton of Manchester, of a family of local repute and good position.
He early took up the pursuit of astronomy with great ardour. He was an exact calculator, discovered defects in the tables of Lansberg and other continental astronomers, and simplified the Rudolphian tables and converted them into decimals. When he entered into correspondence in 1636 with Jeremiah Horrox [q. v.], he was able to encourage and instruct that extraordinary youth in his celestial observations. Horrox, who was eight or nine years younger than Crabtree, frequently refers to him in his writings in terms of praise or friendliness. After frequent consultation Horrox and Crabtree prepared to observe the transit of Venus on Sunday, 24 Nov. 1639, the former at Hoole and the latter at Broughton. As is well known, the observations were successful, and the two friends were the first human beings that ever witnessed the phenomenon. It is narrated by Horrox that ‘a little before sunset, namely at 35 m. past 3, certainly between 30 and 40 min., the sun burst forth from behind the clouds. He [Crabtree] at once began to observe, and was gratified by beholding the pleasing spectacle of Venus upon the sun's disc. Rapt in contemplation, he stood for some time motionless, scarcely trusting his own senses through excess of joy.’
Crabtree corresponded with William Gascoigne (inventor of the micrometer), Christopher Towneley, and Foster of Gresham College. One of his letters to Gascoigne, dated 7 Aug. 1640, was printed by W. Derham in the ‘Philosophical Transactions,’ No. 330 (vol. xxvii., or vol. v. of Hutton's ‘Abridgment’). It is on the nature and appearance of sun spots, and contains some interesting references to astronomical books which he had read. The death of Horrox in January 1640, on the day before he had arranged to visit Broughton, was a great blow to him, as he himself touchingly records. Little is heard of him after the breaking out of the war, and it is uncertain when he died. In the Manchester church register is the entry ‘1644, Aug. 1. William Crabtree of Broughton, chapman,’ and this is assumed to be the astronomer. Wallis, when editing the ‘Opera Posthuma,’ supposed him to have died a few days after Horrox, but later he was informed, as the result of local inquiries, that he lived till 1652 or 1653. If this is correct, he must have been buried elsewhere than at Manchester. He left a son and two daughters.
Crabtree's observations (dated 1 Aug. 1636 to 18 Sept. 1638) are comprised in Horrox's ‘Opera Posthuma,’ edited by Wallis and published in 1672 and again in 1673 and 1676. They extend from page 405 to 439, and have this special title: ‘Excerpta ex Schediasmatis Guliel. Crabtrii, de Observationibus ab ipso institutis, Broughtonæ propè Mancestriam.’ Sherburne says that they amount to not a tenth part of what he had made; but the unprinted papers have now been lost. In the Chetham Library there is a manuscript believed to be in his hand, entitled ‘A True and p'fect Booke of all the Rates and Taxacons wch concerne this county of Lanc.,’ dated 1650. A similar volume is among the Lansdowne MSS. in the British Museum.
One of the fine series of frescoes in the large room of the Manchester town hall has for its subject the observation of the transit of Venus by Crabtree. It was painted in 1883 by Mr. Ford Madox Brown.
[Palatine Note-book, ii. 262, iii. 17, 52, where Mr. J. E. Bailey has most carefully noted all the information that is available about Horrox and Crabtree; Horroccii Opera Posthuma; Hevelii Mercurius in Sole visus Gedani, 1662, pp. 117, 140; Flamsteed and Wallis's Letters in Corresp. of Scientific Men of the Seventeenth Century (Rigaud), 1841, vol. ii.; Sherburne's Sphere of M. Manilius, 1675, appendix, pp. 92, 117; Worthington's Diary (Chetham Soc.), i. 125, ii. 366, 383; Whatton's Memoirs of Horrox, 1859; Hutton's Mathem. Dict. 1815, i. 375; Grant's Hist. of Physical Astronomy, pp. 421, seq., 454–5; Manchester Quarterly, 1882, i. 313; Gent. Mag. xxxi. 225.]