s of Herodotus, to the Bay of Graine, on the Persian Gulf.
It is referred to by Strabo (xvi.
1052). It has been traced by Colonel Rawlinson from Hit almost to the Bay of Graine.
Herodotus and Pliny mention the canals of Asia Minor.
The first constructed in Europe was probably that dug by Xerxes across the low Isthmus of Athos.
The Greeks attempted to cut one across the Isthmus of Corinth.
Among the early European canals may be mentioned the canal through the Pontine Marshes, made 162 B. C.; and the Fossa Phillistina and Carbonania, dug by the Etruscans, and which derived their water from the Padus, now the Po.
Caius Marius, 51 B. C., constructed the Fossa Marina between Arles and Fos, a haven on the Mediterranean.
Lucius Verus undertook to unite the Saone and Moselle, and also to unite the Mediterranean and the German Ocean by means of the Rhone, Saone, Moselle, and Rhine.
His death prevented the execution of the project.
The great object of the Romans was to incre
recorded not less than fourteen times in the last 1,000 years. Its length varies in different countries, as the facts show and theory had supposed.
Eratosthenes, B. C. 276, attempted the measurement of the size of the earth, by ascertaining the distance between Alexandria and Syene, the differences of latitude between which places he had found to be 1/50 of the earth's circumference.
Some previous measurements are mentioned under armil (which see). Hipparchus of Nicaeea in Bithynia, 162 B. C., laid down a map by the determination of the latitude and longitude of places.
A degree was measured on the shores of the Red Sea by the Khalif al Maimoun, the son of Haroun al Raschid, about A. D. 820.
The exact determination of the length of a degree was considered of so much importance that, in 1735, the Academy of Sciences of Paris dispatched two commissions, one to Peru, the other to Lapland. The latter party accomplished their mission and returned in 16 months; the former party