1) 
and year by year their Right Ascensions are larger than they were 
the year before. Wherefore if we could satisfy ourselves that at: 
some unknown date, long ago, when some event took place, some 
particular star had a known Right Ascension, we could by 
calculating back from his present ar to such ascertained ar, 
determine exactly the at present unknown year in which the 
event alluded to happened. 
This then is what I conceived might be done with respect to 
Stonehenge ; only there would be four stars instead ofone. Andif 
we could satisfy ourselves as to what those four stars were, and 
what were the stations in the Temple from which they were 
observed, then, since their ars must at that time have coin- 
cided with the angles from the East made by those stations 
with those stones and mounds, we should be able, knowing what 
those angles are now, and must then have been, to say decidedly 
what the ars of those stars were, when the stones and mounds were 
placed in position. And then by deducting the then ar from the 
present Ar, and dividing the difference by the star’s annual pre- 
cession, we should be able to determine the date at which the two 
outlying stones and the two mounds were placed there, and we 
might thus assure ourselves when Stonehenge was raised. Our 
business, therefore, is to find out what stars the builders of 
Stonehenge made use of at the Equinoxes, and what were the 
angles from the local East point that the two stones and two 
mounds were intended to show. Then we shall know the ar 
of those stars when ‘Stonehenge was building and consequently 
the date of its erection. 
OBJECTIONS. 
Two objections to my theory have been privately made to me, 
each of a character totally opposed to the other ; and as my replies 
to them contain some things that ought to be brought to your 
notice, I will mention them. One of them took this form. Let 
anyone look out at the immensity of space where the horizon is 
