Page:A Treatise on Painting.djvu/129

 into three principal portions, by transverse tendinous intersections or ligaments, viz. the superior part, and a ligament; the second part, with its ligaments; and the third part, with the third ligament; which last unites by tendons to the Os pubis. These divisions and intersections of the same muscle are intended by nature to facilitate the motion when the body is bent or distended. If it were made of one piece, it would produce too much variety when extended, or contracted, and also would be considerably weaker. When this muscle has but little variety in the motion of the body, it is more beautiful.   muscles which serve either to straighten or bend the arm, arise from the different processes of the Scapula; some of them from the protuberances of the Humerus, and others about the middle of the Os humeri. The extensors of the arm arise from behind, and the flexors from before.

That a man has more power in pulling than in pushing, has been proved by the ninth proposition De Ponderibus, where it is said, that of two equal Rh