[ 96 ] 
fides ; and the clear water only is from the furface of 
the bafon let out into the pits. 
If there be any thing, wherein I may further fa- 
tisfy your lordfhip’s inquiries in this or any other 
matter, your commands fhall moft chearfuily be 
obey'd by 
Your lordfhip’s much obliged, and 
mofl: obedient humble fervant, 
William Henry. 
XIII. The Conftru£iio?i of the logarithmic 
Lines on the Gunter V Scale ; by Mr . 
John Robertfon, F. R. S. 
Read June i3,’T~ TAVING lately had occafionto treat 
XTl on the conftrudtion of the Gunter’s 
fcale, I fearched feveral books, wherein I fufpedted 
were contained the reafons of the common methods 
of laying down the logarithmic lines ufually put on 
thole fcales : but not finding, either from my own 
fearch, or that of my friends, any fatisfadlory account 
of this matter, I drew up the following paper, to 
be laid before the Royal Society. 
The Gunter’s fcale * is an inflrument almoft uni- 
verfally known, and amply deferibed by many writers j 
therefore 
* So called from its inventor Mr. Edmund Gunter, aftronomy- 
profeflbr in Grelham-Collegc, from Match 6, 1619, till his death, 
Dec. io, 1 626. 
