Bulletin of the of Agriculture . f the woods treated and do not seem to bear an importantrelation to the absorptions. In some cases it is possible that thelongitudinal penetrations would have shown a closer relation to theabsorptions if the average had been based on the same number ofspecimens in both series of tests. The penetrations represent the 12 BULLETIN 60G, U. S. DEPARTMENT OF AGRICULTURE. average of three specimens of each species treated in the penetranceapparatus, and the absorptions are the average of seven specimenstreated in the cylinder. However, a close relation b
Bulletin of the of Agriculture . f the woods treated and do not seem to bear an importantrelation to the absorptions. In some cases it is possible that thelongitudinal penetrations would have shown a closer relation to theabsorptions if the average had been based on the same number ofspecimens in both series of tests. The penetrations represent the 12 BULLETIN 60G, U. S. DEPARTMENT OF AGRICULTURE. average of three specimens of each species treated in the penetranceapparatus, and the absorptions are the average of seven specimenstreated in the cylinder. However, a close relation between penetra-tion and absorption could not be expected in manj^ of the example, species such as red oak and chestnut oak have largeopen pores or vessels which allow the preservative to pass easilyfrom one end of the stick to the other. The wood prosenchyma ofthese species is very difficult to penetrate and treatment resultsmainly in coating the vessel walls with the preservative and not in AVERA<3E ASSfiRPTlOH, KEC (SUK__ KiIITE OAK_ RED HEARTSEECH__ BUR OAK ROCK ELM CHESTNUT SVCAMORE HACKBERRY HICKORY SUGAR MAPLE OAKRED OAK KKITE HEART BEECHYELLOKf BIRCH RED BLACK WILLOWLARGE TOOTH ASPEM- WlliTE ELK GHEES* ASH SLIPPERY ELR3SILVER S!BCH_ REE-GUHS YSKITE ASH SILVER MAPLE EASSWOOP TUPELO GUfSCTLDREUCHERRV-TUPELO CUM Fig. 3.—Comparative absorptions and penetrations. a complete impregnation of the wood substance. Slippery elm haslarge open vessels similar to those of red oak and chestnut oak, butin this case the wood prosenchyma readily absorbs the was therefore possible to secure both a complete penetration and afairly heavy absorption in this wood. In hickory, the large vesselsare almost completely closed by tyloses, but a fairly good penetrationwas obtained on account of the comparative ease with which the woodprosenchyma absorbed creosote. Species in which the tyloses aremore or less irregularly d
Size: 1615px × 1547px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
