hardwood Record — Veneer & Panel Section 



33 



upon the glue. In such cases the glue will granulate 

 eventually and the work pull apai-t. 



Glue that foams at ordinary temperature should be 

 avoided where quality work is required, as glue which 

 shows foam or in which foam does not quickly subside 

 when the solution is not agitated, is apt to contain im- 

 purities. Foam is frequently found in alum dried glues 

 and in the cheaper bone glues. A simple test for foam 

 is to beat a solution of glue with an ordinary egg beater. 

 It must be remembered, however, that often foam is 

 caused because of improper shop practice, such as over- 

 heating. When such is the cause, the user, and not the 

 maker, of the glue is to blame for the inferior product. 



Excessive grease in glue is sometimes the cause of 

 foam, but it more often takes the form of a scum rising to 

 the top of the solution. Its presence is not desirous and 

 shows that the glue was not properly skimmed in manu- 

 facturing. Again, the user must bear in mind that over- 

 heating the solution will cause a scum to rise, and govern 

 himself accordingly. 



Finally, it may safely be stated that methods of using 

 glue are more to be blamed than the glue used. HARD- 

 WOOD RECORD is about to begin a series of articles 

 on panel making practice. These will tend to show some 

 of the errors of glue room work, and should be of interest 

 to all glue users. 



Veneer Made of Yucca Palm 



A California Desert Tree That Is M ade to Serve the Cause of Humanity 



AI.IFORNIA produces about 400.000 square feet 

 ol yucca veneer annually, counting each log-foot 

 1 1-^ ten veneer feet, and it is put to a peculiar use. 

 ] - ihe production is increasing on account of the 

 ^>.ii, liJi ihe latest published figures were compiled before 

 the beginning of the war. TTie veneer goes to factories 

 which make surgical appliances and is converted into 

 splints for reducing fractured bones and holding them 

 in place during the process of healing. 



Information is not at hand as to the method or meth- 

 ods by which the veneer is cut. The sheets are quite 

 thin, and because of the peculiar structure of the wood 

 they look like lattice work or coarse lace when held 

 toward the light. The strength and stiffness of the sheets 

 are remarkable. They may be cut very thin and yet be 

 strong enough to hold fractured bones in place when 

 louna on oy tne surgeon. 



l"he yucca tree is a most mteresting vegetable. It is 

 called a palm in common parlance, but it is really a lily, 

 with an enormous stem, and with flowers not much 

 larger than a buttercup. People usually think of the blos- 

 som of a lily as the principal part of the plant, but it 

 is not so with this yucca. Unless one looks somewhat 

 carefully, the flowers escape notice while the ugly trunk 

 and tough leaves attract all the attention. Many persons 

 who know the plant well by sight suppose it to be a sort 

 of cactus. 



It is a hardwood; as truly a hardwood as oak or ash, 

 though botanically it is very different. There are no 

 annual rings of growth. TTiere is no heartwood and no 

 sapwood. TTie bark is rough and stringy. The tree has 

 few limbs or branches, and no twigs. The foliage con- 

 sists of an ungainly bunch of leaves crowning the top of 

 the trunk, and looking like a torn and wind-whipped 

 umbrella hanging in tatters. The leaves always look as 

 if they were dead, and are usually from eighteen to twenty 

 inches long and quite narrow. 



TTiis peculiar tree is a denizen of the desert. It lives 

 in regions so dry that horned toads will die of thirst. It 



ranges from northeastern Arizona westward across the 

 Mohave desert in California. It gets its botanical name 

 from that region — yucca mohavensis. Travelers across 

 that region by either the Southern Pacific or the Santa Fe 

 railroad pass many miles through forests of the species, 

 if it can be called a forest where the trees are from ten 

 feet to half a mile apart. A few miners and sheep herders 

 live in the region. A few huts for men and corrals for 

 sheep are built of yucca trunks, usually stood on end like 

 pickets. The wind and the driving sand polish the dead 

 trunks smooth and they look like bones. The lattice-work 

 of the wood is exposed in the old weathered boles, for 

 the sand (and ants) destroy and remove all the soft parts, 

 leaving only skeletons of bony fiber. Logs as large as 

 railroad ties may become so dry and so skeletonized and 

 light that a man can handle them with one hand. 



This is the rough stock from which surgeon's veneer 

 is cut. The largest trunks may be two feet in diameter 

 and twenty feet high, but the average size is scarcely 

 half of that. The tree grows from a seed not so large as 

 a grain of oats, and no man knows how many years are 

 required for a tree to reach maturity. The region is 

 almost rainless, and perhaps not one seed in ten thousand 

 lodges in soil of sufficient moisture to cause germination. 

 Once in a while a young yucca starts, and then the long 

 battle for life begins. It is scorched by the sun, whipped 

 by the wind, scoured by driven sand, and pelted by flying 

 gravel during storms, until the leaves are ripped into 

 ribbons and tangle themselves about the top of the trunk. 

 The trees develop trunks when only two or three feet 

 high, and after that the boles grow in height but not 

 much in diameter, no matter how many years or centuries 

 they may survive. There is no way of telling the ages of 

 these trees, since they have no annual rings. Small ones 

 increase in size with fair rapidity, but veterans seem to 

 attain maturity and after that they increase in size so 

 slowly that they seem to remain stationary. 



This yucca (there are six other species) covers a range 

 of thirty or forty thousand square miles; but the trees 



