CHAPTER LV.                               67

the wall. If the moon is in conjunction with the sun,
the white part of her turns towards the sun, the black
part towards us. Then the white part sinks downward
towards us slowly, as the sun marches away from the
moon."

Every educated man among the Hindu theologians,
and much more so among their astronomers, believes
indeed that the moon is below the sun, and even below
all the planets.

The only Hindu traditions we have  regarding the Ya'kub ibn
distances of the stars are those mentioned by Ya'kub IfsiSices^o/
Ibn Tarik in his book. The Composition of the Spheres, ^^^ '^'''''"
and he had drawn his information from the well-known
Hindu scholar who, A.ii. 161, accompanied an embassy
to Bagdad.    First, he gives a metrological statement:
"A finger is equal to six barleycorns which are put
one by the side of the other.    An arm (yard) is equal to
twenty-four fingers.  Kfarsakh is equal to 16,000 yards."

Here, however, we must observe that the Hindus do
not know the farsakh, that it is, as we have already
explained, equal to one half a yojctna.

Further, Ya'kub says : " The diameter of the earth is
2100 farsakh, its circumference 6$g6^-^ farsakh.'"

On this basis he has computed the distances of the
planets as we exhibit them in the following table.

However, this statement regarding the size of the Puiisaand
earth is by no means generally agreed to by all the guptaoii
Hindus.    So, e.g. Pulisa reckons its diameter as  1600 subjet™*'
yojctnas, audits circumference as 5026-^-4 yojctncts, whilst
Brahmagupta reckons the former as 1581 yojctnas, and
the latter as 5000 yojctnas.

If we double these numbers, they ought to be equal to
the numbers of Ya'kub ; but this is not the case. Now
the yard and the mile are respectively identical accord¬
ing to the measurement both of us and of the Hindus.
According to our computation the radius of the earth is
3184 miles.    Eeckoning, according to the custom of our