10 



QUADRANTS 



46. Quadrant. 



Paper on wood. Radius u inches. 

 Henricus Sutton Londini fecit. 



1658. 



Orrery Coll. (37). 



1669. 



Orrery Coll. (41). 



47. Quadrant. 



Brass. Radius 4f inches. 



Hen: Sutton fecit. 



This quadrant is fully described with an engraving of one dated 

 1658, but otherwise similar, by John Collins, ' Accountant Philomath ', 

 in his ' Sector on a Quadrant ' of great use to Seamen and Practitioners 

 in the Mathematiks } 1659. 



Books, too, were not unfrequently illustrated with copper plate 

 engravings of quadrants, which unscrupulous persons used to cut out 

 and mount for use as instruments. In the Christ Church Library there 

 is a case in point. In a copy of M. Dary, Darys Diarie or the Descrip- 

 tion and Use of a Quadrant, 1649, there was such an illustration. There 

 is also a marginal note by a former owner of the book : 



' I have Taken away ye Quadrant or rather I should say ye whole Figure 

 which heere was inserted ; and Pasted it on a Boarde.' G.F. 

 It was a Sutton's Quadrant. 



48. Gunter's Quadrant. 1665. 



Radius \\ inches. Brass : with lateral sights. Ashmolean Museum. 



Inscribed I.W. 1665. (John Worgan) No. 45 A. 1892. 



Constructed for about latitude 51 40'. On the face is a quadrant 

 with divisions numbered i-io-i including a table calendar LY = (leap 

 years) (16)60 to (16)84. D(ominical) L(etters) and Ep(acts). 



49. Gunter's Quadrant. 1690. 



Ivory. Radius 4^ inches. Orrery Coll. 



I. Rowley fecit. 



On stand, with three levelling screws, double sights, pin-hole, and 

 cross thread. 



50. Gunter's Quadrant. ' 



Boxwood. Radius 3! inches. Gunther Coll. 



51. 10 in. Quadrant with Sights. c. 1728. 



The property of Sir William Osier. 



J. M. Kleman Fecit Amsterdam. 



Sights with slits with threads and pin-holes. 



Hour circle with marked I-XII, I-XII. Zodiac circle. Month 

 circle. Two revolving hands or indices. ' Middach Middenacht.' 



A small printed booklet shows that this instrument and tables were 

 specially intended for the use of Herman Boerhaave at his country 



