CH. IV j 
Ultima Thtde 
27 
With the semi-diameter added, the result is almost exactly 
the latitude of the Marseilles observatory, 43 0 18 ' N. 
Such accuracy is remarkable. The next step taken by 
Pytheas was to fix upon the nearest star to the pole as 
a guide for steering the ship. He found that there was 
no star on the pole, but that there were two very close 
to it. These would have been, in those days, /3 Ursae 
Minoris and a Draconis, and Pytheas used one of these 
as his pole-star. During the voyage the latitudes were 
obtained by observation of the longest days. This in- 
volved long detentions at some of the ports. 
The nearest approximation we can get to the date 
of the voyage of Pytheas is the time of Alexander the 
Great and of Aristotle, about 330 B.C. 1 
A Grecian ship in those days was strongly built on 
regular principles, with sails on the mainmast, and rowing 
power. A large vessel would be 150 to 170 feet long, 
with a tonnage of 400 to 500, much larger and more 
seaworthy than the crazy little Santa Maria in which, 
1800 years afterwards, Columbus discovered the New 
World. 
Well provided with all the knowledge of his time, 
Pytheas weighed anchor and began his coasting voyage 
by the Pillars of Hercules and the Sacred Promontory, 
the western limit of the known world. The Greek 
ships of the time averaged about 50 miles a day. 
Sailing on along the coast, Oestrymnis (Cape Finistere) 
was reached, the probable farthest point of Himilco the 
Carthaginian. The island of Uxisama (Ushant) is men- 
tioned, with an observation for the length of the longest 
day equal to 49 0 N. Thence a direct course was shaped 
for Cantion (Kent) where there was a long stay, and the 
island of Britain was thus discovered. Here Pytheas 
made a long journey into the interior, visiting Belerion 
(Cornwall) and the tin mines, and noting several details 
respecting the habits and customs of the people, our 
remote ancestors. In those days Britain was almost en- 
tirely in a wild state. The valleys were covered with 
primeval forests, their lower parts were occupied by 
1 The work of Pytheas was known to Dicaearchus, a pupil of Aristotle, 
and the date of the voyage was, therefore, probably not later than the 
time of Aristotle. 
