For reading lessons the poets were chiefly used, and their writings were inscribed in manuscripts which were either rolled or folded. (Compare Fig. 75.) Homer was used as the school book of the Greeks, from the earliest periods to the fall of the Byzantine Empire, and his writings were read and expounded, as well as other poems in various metres, chiefly of a lyrical character. The master then either gave the boys copies, which he had probably made himself, or else, if they were already able to write, dictated longish passages to them; the pupils also had to learn a good deal by heart. Many teachers prepared anthologies of various writers for reading purposes; those especially were chosen which by their contents were well adapted for the reading of youth, such as Hesiod, Theognis, Phocylides, etc. The boys thus, by their reading and learning, acquired a knowledge of mythology, while at the same time the most important ethical principles were impressed on them. We must be careful not to rate too low the results of this instruction, however little we may think of the Athenian acquirements in the mechanical arts of reading and writing. A people who knew how to appreciate the tragedies of Aeschylus, who could understand the comedies of Aristophanes, with their fulness of mythological, literary, and political allusions, must have possessed a degree of culture which in many respects was far above the average of the present day. It was, of course, easier for the pupils to acquire a large amount of mythological and literary knowledge when there were so few subjects to study; since natural science, geography, history, and foreign languages were all disregarded. In reading, the elements of prosody were also learnt, and these were more fully treated in the musical instruction. We are no longer in a position to state how arithmetic, with whose practical uses the ancients were naturally well acquainted, was taught; but it is probable that--at any rate at Athens--this instruction was given at home and not at school, and was acquired by children in play by means of concrete objects, which enabled them to learn the principal notions and relations. As regards method, counting on the fingers was very common in Greece. The left hand was used to represent all the units and tens, and with the addition of the right hand all the hundreds and thousands; the mode in which a finger was placed on the open palm and the number of the fingers, which were either bent or stretched out, determined the number required. More complicated calculations were performed by help of an _abacus_ with little stones, an ancient invention long known to the Egyptians, in which the arrangement of the stones in the parallel lines on the board determined their value as units, tens, hundreds, etc. We do not, however, know anything further about the arrangement of the Greek abacus.