[ii(J8] 
the Moon then ftiining) he found tobe ^4'*. i'. ff". the 
lame exadly, even to feconds, which he had, before, 
fix timesobferved inthe years idfS. 1661. i(57i. Where- 
at Mr. Ha l/y hting much furprifed, fas not expeding 
,that accuracy,) it was again for his greater latisfadlion 
(that he might not think it only a great good- hap) 
obferved the fame exa£tly, June. i. and again June. 7. 
Many more obfervations were made from day to day, 
during all the time of his abode there, fuch particu- 
larly as Mr. Halfy (for his fatisfadion ) did dired:. To 
which he attended conftantly, and didftridly examine 
them, with great diligence and curiofity j that he might 
not by any miftake be impoled upon. Which obfer- 
vations are all, here, particularly fett down. And a^ 
mongfl the reft, (to compare the^ accuratenefs of the 
two forts of Sights^) a lift of divers obfervations made 
by the Author ("with a fmall Inftrument and common 
Sights,) and the fame made by Mr. //^^ ("with a much 
larger and Telefcopick^ Sights: ) By which the Author 
thinks it will be evident to an indifferent Judge, that 
thofe performed by the Plain Sights^ (though in a fmal- 
ler InftrumentJ are the more accurate. And doth 
ferioufly profefs, that he could not with Mr. Hally % 
Inftrument (though he did truly endeavour itj make 
obfervations with that accuracy and that readynefs, as 
with his own. 
Upon the whole matter, Mr. Hallj finding all much 
to his fatisfadion, and beyond his expedation, thought 
fit to leave in writing his Atteftat ion thereof, (inform 
of a Letter to the Author] dated July^ 8, 18, 1(^79 J 
wherein he declares himfelf abundantly fatisfied of the 
ufe and certainty of thefe his Injiruments and Obferva*- 
tions^ And whereas he bad, before been always doubt- 
fully that his obfervations by naked Sights mighty as to 
fome Minutes, be uncertain i and had therefore rvondered: 
-why he declined the ufe of Telefcopick^ Sights-^ (though 
ytt^ 
