Trigonometrical Survey. 541 



the great number now published, instances may not be found 

 of misnomers, or even wrong bearings ; but I rely with great 

 confidence on their general accuracy, and particularly on those 

 constituting the surveys of Essex and the northern shore of the 

 Thames, as the whole of them have beenverifiedby Mr. Gardner. 

 Indeed this is to be understood as holding good throughout the 

 last section, in which are 375 triangles. In our former accounts 

 of this survey, we were particularly guarded in not intermixing 

 their contents with distances determined from numerous doubtful 

 intersections ; and experience has hitherto not detected above 

 three or four errors arising from wrong bearings or misnomers. 

 Previously, indeed, to the compilation of them, a great part of 

 the objects in Sussex, Hampshire, and the Isle of Wight, were 

 verified by Mr. Gardner, in process of an extensive survey, car- 

 ried on by the order, and performed for the service, of the Board 

 of Ordnance. This gentleman will also have it in his power to 

 detect any errors, if such exist, in the names of places to the 

 westward; as the Master General has been pleased to issue his 

 directions for the survey of Devonshire, and as much of Somer- 

 setshire and Cornwall as will square the work. 



I have mentioned, in the body of the account, that the Presi- 

 dent and Council of the Royal Society, were pleased to accede 

 to the request made by the Honorable Board of Ordnance, to en- 

 trust to my care, the circular instrument used by the late Major 

 General Roy, in his well known operation. It has already been 

 found highly useful^ and will shortly prove to be still more so, 

 as one theodolite will be employed in carrying the above orders 

 of Marquis Cornwallis into effect, while the other is used 

 in carrying a meridional line through the country ; an under- 

 taking begun, and partly executed. 

 mdccc 4 A 



