HARDWOOD RECORD 



47 



the result of still more exhaustive iuvestigations b}' a German 

 mjcologist iu Munich, it has beeu found that the appearance and 

 development of a blue stain fungus on a board is determined wholly 

 by the relative amount of air (and consequently of water) contained 

 in a given volume of freshly cut wood. Stated in exact terms, it 

 lias been found that if the air space occupies only 15 per cent, of 

 the volume of freshly sawed wood, the blue stain fungus cannot 

 possibly grow on it. If a freshly cut board dries out so that it 

 loses lU to 15 ijer cent, of its weight, the conditions are then of 

 such character that the blue stain fungus grows with great rapidity. 

 On the slide before you, you will see some photographs of blocks 

 of wood inoculated with the blue stain fungus. The table below 

 shows the percentage of air and water in each particular stick. 

 Vou will note that stick No. 1, having only 15 per cent, of air in 

 it, has no stain on it at all, and that as tht percentage of air 

 increases in the stick, the amount of stain increases. This with 

 the exception of the last piece in which the percentage of water 

 becomes so small that the growth of the fungus was considerably 

 letarded. The most favorable condition for its development is 

 when the wood contains about 40 to 42 per cent. air. In freshly 

 sawed lumber the percentage of air in the outer layer undoubtedly 

 rises above 15 per cent, very soon after the boards are cut. I regard 

 this recent discovery of the relation of the air content to the blue 

 fungus as extremely important and a decided step in advance. It 

 now remains to go still farther and determine the relation between 

 this fungus and the acid production on the outer surface of the 

 board, and what relation these two factors bear to the compounds 

 whicli we are trying to use to prevent the stain. I do know that, 

 without appreciating the causes, we can stop the stain with certain 

 ciiemical salts, but I would advise caution in applying these salts 

 \\\cept under the most rigid conditions. 



We are preparing at the present time to inaugurate a series 

 of accurate observations at the sawmills with whom we are working, 

 not only to reduce the cost of operations but also to increase their 

 ♦■Ificiency. 



III. This brings me to another item of saving, namely, the question 

 of handling crossing strips. Hundreds of thousands of feet of 

 lumber are manufactured into crossing strips at the mills every year, 

 and in tlie majority of cases these crossing strips rot, break and 

 are thrown away. This represents the loss not only of the lumber 

 manufactured into the crossing strips, but also a very considerable 

 loss due to the contaminating influence of tlie crossing strips to the 

 boards on both sides of them. 



During last year we built a small plant for the treatment of 

 crossing strips at one of the southern mills, and it is the plan 

 to hereafter treat all crossing strips so as to make them last a 

 sufficiently long time to pay for the strips themselves, and at 

 the same time to save lumber. 



I want to make it very clear that the treatment of crossing strips 

 is a very different proposition from the treatment of lumber to 

 prevent sap-stain. Xot only must different chemicals be used, but 

 the process must be conducted in an entirely different manner so 

 as to avoid not only loss of treatment, but also probable loss of 

 the lumber from piles in which improperly treated sticks are used. 



I want to caution all manufacturers against the use of salts or 

 compounds which might in any way influence the grade. I, per- 

 sonally, for instance, would discourage the use of mercury chloride 

 in any way in the treatment of boards to prevent stain. The use 

 of small quantities may be justified, but 1 would by no means make 

 it a matter of general application. 



IV. A problem, which is giving a good deal of trouble to cotton- 

 wood manufacturers, is the so-called "brittleness" of a considerable 

 i|uantity of this timber after it has be«n sawed into boards. Com- 

 jjlaints of this kind are coming from all parts of the Cottonwood 

 manufacturing district, and have also been received from one of 

 the large mahogany dealers. 



Examination shows that this cottonwood is perfectly sound, that 

 is, there is no decay in the fibre and to all intents and ptirposes it 

 should not break. We had an idea that it might be due to long 

 exposure of the wood in water. Some tests were made during 

 the last two years by immersing certain pieces in water, and keeping 

 other pieces from the same log in a dry room. The pieces were 

 soaked about two years. They were recently tested under a testing 

 machine, and to our surprise it was found that the difTerence be- 

 tween the soaked and unsoaked pieces was only such as might occur 

 iu two different sticks of wood. In other words, soaking the wood 

 had apparently not harmed it. It will therefore be necessary to 

 make further investigations to determine what causes this brittle- 

 ness. It is certainly becoming an important problem to the cotton- 

 wood manufacturer. 



V. One of the chief difficulties in the manufacture of many hard- 

 woods to-day is connected with the drying operation. As a rule 

 carefully air-dried lumber is far to be preferred to lumber dried 

 in any other way. It is, however, not practicable in many cases 

 to air-dry the lumber — in the first place, because the time necessary 

 for holding lumber in order to air-dry it means a considerable 

 investment tied up. and in the second place, it may oftentimes be 



more profitable to kiln-dry lumber in order to prevent sap-stain. 

 Kiln-drying is something that will be resorted to and which will 

 probably be used on an increased scale in the future. A whole 

 evening, or for that matter, several evenings might be devoted to the 

 discussion of this subject. All I can do now is to call attention 

 to the necessity for careful study of the kiln-drying operations. 



There are a large number of kilns on the market, whose claims 

 go all tlie way from rapidity to efficiency. I have recently tested 

 some lumber for the Cypress Association dried in different kinds of 

 kilns, which may serve as a striking example of what a kiln can 

 do and cannot do. Without mentioning any names, you will be 

 interested in seeing the results of exceedingly rapid kiln-drying when 

 compared with slower kiln-drying tmder entirely different conditions. 

 I hold that perfectly dried lumber is the best product whicli any 

 mill can possibly turn out, and in order to do this, more attention 

 must be given to the subject of the dry kiln. 



Practically everything we know about kiln-drying lumber has 

 lieen learned by very great eff'ort, and what we now need is careful 

 comparative examination of the various kinds of kilns and the 

 results which can be obtained with the different kilns with different 

 species of hardwood lumber, for what may be true of cottonwood 

 drying will not hold for gum. I believe that you will readily ap- 

 preciate this when you think of the very complex structure of the 

 different woods. Note, for instance, the difl^erent arrangement of 

 the wood cells in pine and oak. 



Drying means the slow disappearance of water, carried from 

 cell to cell to the outside. Any drying process which dries the 

 wood in such inaiiuer that it does not split, clieik, warp or twist, 

 must ili'v it at tlie rate of speed with whicli the water travels 

 from tlie interior of the stick to the outside. This cannot be i!c- 

 termined theoretically, nor can it be determined by argument, iiur 

 can it be determined by the test of one or two small pieces, but 

 it must be determined on a large scale and under every possibly 

 varying condition as to locality and kind of lumber. If there is 

 any one thing which will do more than any other to increase the 

 (luality of the lumber turned out, it is successful kiln-drying. I 

 get more inquiries from manufacturers asking how they can suc- 

 cessfully dry gum, cottonwood, etc., etc., and I am sorry to say 

 that f am unable to answer these ipiestions as I would like to, because 

 llic information is not as yet at hand. 



VI. Intimately connected with the manufacture of lumber, as 

 an item of possible future economy, is the question of possible 

 chemical treatment of all the lumber and timbers used by the 

 manufacturer himself. All of the larger railway companies, tele- 

 graph and telephone companies, etc., are now using chemically pre- 

 served ties, poles, posts, bridge material, etc. The rapidly decreasing 

 supply of such timbers and the consequent increase in prices have 

 brought most of us to the realization of the necessity for such action. 

 The lumber manufacturer, who uses timber from his own lands for 

 making ties for his logging road, particularly if these timbers are 

 capable of being manufactured into lumber, is depleting his own 

 stock to that extent. 



One of them recently said to me: "My supply of tie timber is 

 getting low, and I am getting about two to three years' life out 

 of the ties in my logging road. Is there not something that I can 

 do to increase the length of life of these ties, not only for the 

 purpose of saving the cost of the new ties, but also the very expensive 

 cost of renewal charges?" He is now building a small treating 

 plant where all of his logging track ties will be treated from now on. 

 What is true of logging roads will apply also with equal force 

 to telephone and telegi'apli lines, building foundation timbers, sills 

 for trucking platforms, etc. A little expense at the right time means 

 a big economy in the long run. ily particular treating plant at 

 the Missouri Botanical Garden, where I can treat pieces of logs, 

 shingles, etc., bas cost to date the magnificent sum of $1.75. 



If the time permitted, I would like to dwell on other phases 

 of the manufacture of lumber, for instance, the possibility of en- 

 gaging, either directly or indirectly, in the production of stained 

 wood or the so-called artificial wood. Numerous concerns are now 

 advocating processes of various kinds to unsuspecting manufacturers. 

 I was particularly imjiressed recently by one man, who sent out 

 circulars on a process for staining wood upon which he claimed to 

 have a patent. The manufacturer, fortunately for him, brought the 

 scheme to us, and was very much surprised when I showed him a 

 list containing some one hundred or more patents on the same 

 subject, many of which were issued si.xty or .seventy years ago. 



VII. Before closing I must refer briefly fo the question of bi- 

 product plants. 



Under the present market conditions, with prices down on wood 

 alcohol and charcoal, etc.. even when successfully operated, the 

 bi-product plant in the Mississippi Valley is not a very satisfactory 

 proposition. One of the chief reasons why none of the bi-product 

 plants have succeeded is undoubtedly due t-o the fact that they 

 have been ojierated by men entirely unfamiliar with the industry. 

 What the average manufacturer does not know about retorts, distils, 

 etc., would fill a book. Many of the bi-product plants which I have 

 examined in recent vears ought to have failed. While condemning 



