36 HOUSE, GARDEN, AND FIELD 



the flexors of the fingers, long, slender tendons, popularly 

 called " leaders " or " guiders," which lie close to the 

 bones, being held down by cross-bands and sheaths. On 

 the back of the hand, near the knuckles, you will see 

 another set of tendons, which become most evident during 

 extreme extension of the fingers. At the base of the 

 thumb two extensor tendons are quite plain. 



Since you are not able to dissect a hand, and trace the 

 tendons which move the various parts, I would advise 

 you to get a fowl's foot, strip off the skin, and look at 

 the tendons of the toes. On that side of the leg and foot 

 which joins the sole, you will find a large flexor tendon, 

 which sends branches to the four toes. When it is pulled 

 the toes become bent. On the other side of the leg and 

 foot is a branched extensor tendon, which raises and 

 spreads the toes. You can learn from this example what 

 a tendon is a smooth, very strong, white, shining, fibrous 

 cord, which is firmly united to a bone. It often lies in 

 a glistening sheath of the same fibrous substance, and 

 may be prevented from slipping out of its place by cross- 

 bands ; the sheaths are plainly seen in the fowl's foot. A 

 tendon is always attached to a muscular or fleshy mass ; 

 without muscular fibres there would be no contraction, no 

 pull on the bones. The tendon itself cannot originate a 

 pull ; it can only transmit it. If you bare your forearm, 

 grasp it near the elbow, and then flex the hand, you will 

 feel the muscles swell ; during contraction they become 

 shorter and thicker. This will convince you that the 

 flexion of the fingers is not caused by contraction of 

 muscles in the fingers or in the wrist, but almost entirely 

 by contraction of muscles in the thick part of the fore- 

 arm, near the elbow. If the muscles which flex the hand 

 and fingers were placed close to the bones on which they 

 act, the hand would be a large, soft mass, and the fingers 

 so clumsy as to be incapable of rapid, precise and com- 

 bined movements. The sheaths and cross-bands hold the 

 tendons close to the bones during flexion. How awkward 



