166 IJ'riglit ^c. on an Universal Measure; 



the arch of the great circle, or shortest distance betwixt 

 them, together with the angle of declination thereof from 

 the true nienuian line truly found by observation at either 

 'of those places, may most exactly be knowne : whereby 

 (with hcipe of the doctrine of right angled sphEericall tri- 

 angles) the difference of the latitudes of thobc two places, 

 in mile.N and furlongs, &c. may easily appeare; which com- 

 j*arcd with the difference of the latitudes of the same peaces, 

 fVmnd bv observation of the Sun, in degrees and minutes, 

 &c. will shew how many miles and furlongs answer to one 

 or more degrees of the meridian : and so the whole circum- 

 ference, diameter and semidiametcr of the earth, will easily 

 and more truly be found, then any other way yet used for 

 this purpose. But meancs convenient for the triall hereof 

 have hitherto been wanting, and so I must omit it, till 

 Some better opportunity, if any shall befall hereafter, by 

 the bounty of any such as are of more ability to bear the 

 charjre hereof. 



" Yet besides our purpose now in hand, this would bee 

 the best ground that can be, both for the making and con- 

 tinuing of a Standard, and all other measures thereon de- 

 pending at a certainty forever; insomuch that althougfi all 

 the Standards, weights and measures in the world were lost, 

 they might, notwithstanding, upon record of such obser- 

 vation and means, as here we have mentioned, be again 

 Restored much more perfectly, thtnby the ordinary way of 

 beginning all our measures from a barly grain taken out of 

 the midst of the Ear, thereof there is no such certain de- 

 terminate bignesse that can be set down, but that they may 

 be something greater in one Ear then another ; neither can 

 there be any certain rule or reason given how to know 

 which Ear to chuse rather then other for this purpose. 

 And if any error be committed herein, though insensible 

 (which cannot be avoided) yet in going about to inake 

 other greater measures by often taking this least, and so 

 proceeding a minhnis ad maxima* , so often as you take 

 your lirst or least measure, so often doe vou increase and 

 multiply your error; which though at first it seem very 

 smal and scarcely perceivable, yet commeth at the last to 

 be very notorious and intollerable. But the other way I 

 here speak of, taking the length of all England, or of the 

 whole Hand, for our first measure, and out of it bv subdi- 

 vision, dividing all the rest, although wee may erre some- 

 thing, in taking the length hereof (which notwithstanding, 



» From the least to the greatest. 



■^ I dare 



