31 



WORK AT THE TEST LABORATORY AT ST. LOUIS, MO. 



(Wriltcii liy rrof. .1. I!. Jdii.vsuX.) 

 SAWIMG, STOKING, AND SEASONING. 



On arrival ulilic lo^s in St. Louis tlu'val■(^ sent to a> .sawmill and cut iiitu sticks, as sIkiwh in 

 Figs. 1 to 4. 



In all cases the arraiiucnicnts shown in Fius. 1 and L.' arc used, cxcc])t when a detailed stiulvol" 

 the tiuil)er in all parts of the cross section ot the loi;- is intended. A few of the most iicrfect logs 

 of each species are cut up into small sticks, as shown in I'igs. .3 and 4. The logs tested foi' deter- 

 mining the effects of extracting the turpentine from the Southern jiitch i)ines were all cut into small 

 .sticks. 



In all cases a " .small stick" is nominally 4 inches .square, but when dressed down for testing 

 maybe as small as 3i inches s(iuare. The "large sticks" vary from (I by ll' to S by k; inches in 

 cross-section. 



All logs vary from lli to 18 feet in length. They all have a north and south diametral line, 

 together with the number of the tree and of the log plaiidy ni;nked on their larger or lower ends. 



The stenciled lines for sawing are adjusted to this north and .south line, as shown in the figures. 



•>5 



Each space is then branded by deep dies with three numbers, as for instance thus: "2, which signi- 



4 



fles that this stick was number 4, in log 2, of tree 25. A facsimile of the stenciling is recorded in 

 the log book, and the sticks there numbered to corres]>ond with the numbering on the logs. After 

 sawing each stick can be identitied and its exact origin dc^termincd. These three numbers, then, 

 become the identification marks for all .specimens cut from this stick, and they accompanx the 

 results of tests in all the rec(U'ds. 



The methods of sawing .shown in Figs. 2 and 4 are called ''boxing the heart;" that is, all the 

 heart portion is thrown into one small stick, which in practice may be thrown away or put into a 

 lower grade without serions loss. In imi)()rtant bridge, lloor, or roof tindiers, the heart should 

 always be either excluded or "boxed" in this way, since its ])resence leads to checking :ind impairs 

 the strength of the stick. 



After .sawing, the tiinbers are stored in the laboratory until they are tested. The "green 

 tests" are made usually within two montlis after sawing, whilethe "dry tests" are n)ade at various 

 subsequent times. One end {(iO inches) of each small stick is tested green, and the other end 

 reserved and tested after seasoning. The seasoning is luistened in some cases by means of the 

 drying box shown on Plate i. Thetem])eratureof the inllowing air in this drying box is kept at about 

 100° F., with, suitable precaution against checking of the wood, and the air is exhausted by means 

 of a fan. The air is, therc^ibre, .somewhat rarefied' in the box. The temperature is at all times 

 under control. It operates when the fan is running, and this is only dui'ing working hours. 



