994 



AMERICAN FORESTRY 



bent under pressure will keep the shape given it. Elas- 

 ticity is found in flexible woods like ash and hickory 

 and in stiff woods like pine and spruce. A floor beam 

 should be stiff and elastic; a carriage axle should be 

 flexible and elastic. 



Flexibility-Stiffness: As an archer's bow so must the 

 felloe of a buggy wheel be flexible, elastic and tough. 

 For the buggy wheel hickory answers best; for the 

 bow ash is chosen because it is lighter and does not 

 "set" so readily. No one would choose a flexible wood 

 for a bridge stringer, or 

 for a car sill, but one 

 which is stiff, strong under 

 a load, durable and not 

 too heavy. 



Hardness is of import- 

 ance when the service re- 

 quired of a wood tends to 

 cut into it, or to wear it 

 down. A railroad tie must 

 resist the cut of the rail ; a 

 floor board not covered 

 with a carpet must with- 

 stand wear. A door of 

 soft -vod is better than 

 ^ .^ ot " rd wood because 

 it is ligi *J and hardness 

 gives it io advantage. 

 The best fl oring is "quar- 

 ter sawed' to show "edge 

 grain" because that face 

 wears better than a com- 

 mon face sawed "through 

 and through." In ordi- 

 nary carpenter work hard- 

 ness is a disadvantage as 

 it increases the labor re- 

 quired with no correspond- 

 ing gain. 



Shrinking: The wood 

 that shrinks, or works, 

 least is always preferable, 

 top that shrinks after it is finished will show an un- 

 sightly crack unless provision is made to conceal the 

 contraction. Floor boards are made narrow partly to 

 expose the edge grain, but chiefly to neutralize shrink- 

 age. If an eight-inch board shrinks a quarter inch 

 there is an appreciable space between it and the next. 

 If the eight inches are covered by four boards the gap 

 between each is only one-sixteenth of an inch. 



Woods differ in this quality according to their struc- 



WOOD WHICH TWICE OUTLIVED STEEL 



White oak tie, side view This tie was laid in the track during the 

 year 1888. The steel has been changed twice since that time. The ties 



have decayed but little anc! will probably serve 

 or five years. Plains, Montana 



A carriage panel or a table 



ture, and for particular purposes must be chosen with 

 reference to it. But apart from that the moisture con- 

 tent is of great importance. In some species the green 

 wood may contain as great a weight of water as of 

 wood substance. In any species seasoning causes the 

 water to be evaporated and the wood to contract. In 

 genera! the coniferous, or soft, woods shrink less than 

 the hard, deciduous, woods. 



W eight: Our common woods vary from 22 pounds 

 (white cedar) to 53 pounds (hickory) per cubic 



foot air dry. Where 

 strong timbers are to be 

 used near the point of 

 production, weight can be 

 ignored. When cost as 

 well as quality must be 

 considered the transporta- 

 tion of a heavy wood 

 handicaps it. But in some 

 cases weight is vital : air- 

 plane wings, for instance, 

 are framed of selected 

 spruce because that wood 

 possesses considerable 

 strength and stiffness com- 

 bined with extreme light 

 weight. Ash likewise is a 

 preferred wood where 

 strength, toughness, elas- 

 ticity and a minimum 

 weight must be com- 

 bined. 



Other qualities, as den- 

 sity, tastelessness, etc., are 

 sometimes of importance. 

 A tight barrel can be made 

 of white oak, but not of 

 red oak because the latter 

 contains numerous open 

 vessels or "pores." Con- 

 tainers and implements 

 used for food stuffs must be made of wood that imparts 

 no taste. Thus butter tubs and oyster pails are made 

 of spruce, or ash, or maple. 



No user of wood doubts that its manifold qualities are 

 advantages rather than faults, since only through them 

 can the forest product, wood, be made to satisfy so many 

 human needs needs that range from the coarse, solid 

 endurance of a railroad tie, through the soft, weather- 

 proof, roof shingle to the light, stiff and strong wing of 

 the mechanical bird. 



side track for four 



One of the members of the American Forestry Association desires to locate a tract of about one thou- 

 sand acres in New York State, within 150 or 200 miles of Buffalo, for hunting, fishing and vacation pur- 

 poses. Valuable timber is not essential cut-over land preferred. Information will be gratefully received 

 and promptly forwarded. Editor. 



