814 



AMERICAN FORESTRY 



first place. It possesses certain characteristics that are 

 wanted, and it has them in a higher degree than any 

 other known wood. It is Hght in weight, a requisite 

 which cannot be insisted upon too strongly; it is very 

 tough, not easily split or splintered under blows and 

 twists, and not apt to check or warp in process of 

 seasoning. After it has become dry it shrinks and swells 

 but little. The pores in the wood are very small and 

 impurities are not readily absorbed. It cuts easily, and 

 therefore lends itself readily to the shaving and whittling 

 which the manufacturer must do in converting the rough 

 billet into the finished limb. Some of the cutting is done 

 by machinery, but much is hand work with special tools, 

 in hollowing the inside and shaping the exterior. The 

 limbs are hollow. They are thin shells, and willow wood 

 is so tough and strong, in proportion to its weight that 

 the shells can be whittled very thin. They are then 

 covered with raw hide, the kind of leather that forms 

 the heads of drums, and the final coat of varnish is 

 applied to the leather. The necessary metal and other 

 fastenings can be 

 affixed securely to 

 this thin shell. 



The breaking of 

 a wooden leg is a 

 serious matter, 

 though not so ser- 

 ious as the fracture 

 of a bone of a natural leg, and 

 it is less painful ; yet some pain 

 of a pecuniary kind may be oc- 

 casioned by the knowledge that 

 a broken willow leg may cost a 

 hundred dollars in repairs. 



The suggestion has been made 

 that false limbs might be made 

 of woods other than willow ; and 

 so they might be and so they 

 have been. Willow is not the 

 lightest wood in this country. A 

 dozen others are as light or 

 lighter; but lightness is not the 

 sole quality to consider. If it were, the first place 

 among American species would go to Missouri corkwood 

 (Leitneria floridana), and tupelo roots would be available, 

 and also the golden fig of Florida, or several of the 

 cedars. But, on account of undesirable physical quali- 

 ties, not one of these is a rival of white willow in the 

 wooden limb industry. 



Many attempts have been made to find substitutes for 

 wood ; not that cheaper material is wanted, but in some 

 instances it is difficult to fit a wooden limb satisfactorily 

 and other materials would be more convenient. That 

 none of the substitutes has been wholly satisfactory is 

 evident from the fact that wood continues to be the most 

 widely used material for manufactured limbs. Gold has 

 been mentioned among other substitutes, but perhaps 

 reference to that precious metal in Thomas Hood's poem 

 was not meant to be taken seriously. If gold were as 



Inventors ha 



cheap as willow, it still would not often be employed for 

 this work, because it is too heavy and too weak. Alumi- 

 num would be better than gold, but it has had little use, 

 although it is claimed that the former German Emperor's 

 withered arm has been concealed incide a hollow alumi- 

 num mechanism that passes for an arm. 



Fashion has more to do with false arms and legs than 

 might be supposed. Some wearers are as proud of theirs 

 as smokers are of favorite pipes, or sportsmen of guns 

 which break records, or fishermen of reels which land 

 the largest and gamest fish. Some patrons of the limb 

 factories buy new arms or legs nearly as regularly as they 

 buy new clothes ; not that the old are worn out, but 

 fashion, as they think, demands new outfits at regular 

 intervals. Besides, it is good foresight to have a new 

 member ready for use if the old should become incapaci- 

 tated by accident. 



Crutches are with reason included in the limb industry, 

 for both are put to the same use in assisting cripples to 

 carry on the afi'airs of life ; but the points common to the 

 two products go little farther than 

 the methods in which they are used. 

 The processes of manufacture are 

 different, so arc the woods employed. 

 The crutch maker 

 needs very hard 

 and very strong 

 woods, and weight 

 is not objection- 

 able ; but the limb 

 manufacturer must 

 have light wood, 

 yet it must be 

 strong, and he has 

 few species to 

 choose from. The 

 crutch maker has a 

 pretty wide field of 

 choice. 



New Hampshire 

 leads all other 

 states in the pro- 

 duction of crutches so far as statistics show. Birch 

 and maple, which are excellent woods for crutches, are 

 abundant and of fine quality in New Hampshire. Choice 

 woods like cherry, rosewood, and lancewood, find a place, 

 the first two as handles or grips and as tops to fit under 

 the wearer's arms, and lancewood, because of its strength, 

 becomes the shaft. New Hampshire produces about 250,- 

 000 pairs of crutches a year. The best grades are made 

 of sugar maple with rosew^ood handles. 



If canes were admitted into the artificial limb indus- 

 try, the number of woods to be listed, and the total 

 quantity, would be much increased. Cane makers con- 

 sume about 2,000,000 feet of wood a year, in addition to 

 some woods which are never measured in feet, such as 

 weichsel, bamboo, and nannybcrry. 



The wearing of artificial limbs is not restricted to any 

 condition of life, to any size of persons, or to any age. 



THE MECH.\NISM OF ARTIFICIAL ARMS 



worked faithfully on the problem of producing acceptable sub- 

 stitutes for the human arm, and the accompanying illustrations show some of 

 the results of their genius and labor The problem has many angles that must 

 be taken into account, and many ideas have been successfully developed.' 



