1 Exact determination of botanical origin.
This is one of the most difficult requirements to fulfill. Since it is very nearly impossible to verify the precise botanical origin of any specimen obtained from a lumber-yard, from the work shop of a cabinet-maker or any similar source, it means practically- especially in the view of point 2- that every sample ought to be taken from the living object. Only in this case, inasmuch as leaves, flowers, seeds and the like can be obtained from the same tree, will it be possible to guarantee an exact and scientifically correct determination. Even if the collector is not sufficiently trained as a botanist or if the necessary literature is not available he can always have the foliage specimens determined by an expert at a later date, especially if he can state where the tree came from.
Although the examination and comparison of microscopic sections usually enables the scientist to establish the exact genus, or at any rate, the family to which the specimen belongs, it is very often impossible to discriminate between species, since, in numerous cases, the structural difference between two closely related species (such as the oaks, willows, poplars, pines and the like) is less pronounced than variations in one species due to conditions of climate and soil.
2 Precise labeling.
Each specimen should be carefully and properly labeled, the label containing the following specifications:
a Common or most generally used trade name.
b Latin or botanical name.
c Locality of where specimen was taken.
d Native land or natural distribution.
(Here was attached a type-set label in very small letters---3/8xl".)
Rhamnus californica Eschsch.
West Coast of North America.
I have found it advisable to print the labels with the smallest available type and to fasten them to the underside of the samples in order not to mar the beauty of the visible side.
If one wishes to make more extensive notes on each sample, as, for instance, concerning the age of the tree or whether the specimen was taken from the base of the trunk or near the top etc. a special file can be established as a supplement to the labels. In this case the same label should be pasted on the file card, whereas the supplementary notes can be typed or written. It is also possible to give each specimen a number, the number on the label and the file-card being identical.
3 Choice of specimens.
In order to display the characteristics of the normal grain both plain and quarter-sawed specimens should be used. One of them can include a small amount of sapwood, which, especially with nearly all tropical woods, is quite distinct from the darker colored heartwood.
(Here Dr. Mautz illustrates with three neat sketches showing where the specimens were obtained by depicting the end of a log. It will be too difficult to reproduce on this stencil. He refers to the specimens as so-called tangential-longitudinal and radial-longitudinal.)
The specimens should be selected not only in view of proper sectioning but care should also be taken that each piece is without flaws or imperfections of any kind such as cracks, knots, worm-holes and the like. The color should correspond to the coloring of healthy, mature and properly seasoned wood, special consideration being given to the fact that the sapwood is not streaked or grey, due to improper seasoning or because the sample was not cut directly after felling. Furthermore samples should only be taken from the trunk of the mature trees, not from the branches or young saplings.
[Note: the above recommendation of collecting samples only from a mature trunk, and not from branches or young saplings, has proven quite unfeasible to most collectors over the years, I imagine. Many landowners who would gladly allow samples to be collected from branches or saplings would likely frown at the collector asking to saw down the entire tree...cdr]
The size of the specimens depends more or less on how they can be arranged and on the total space available for the collection. It is advisable not to choose too small a size etc. etc. (Here the editor takes the liberty of calling attention to the standard size already adopted by the large majority of collectors -- 1/2 x 3 x 6" -- so in order not to confuse the members we will delete his recommendations which call for two or more sizes, the largest being 1/2 x 3 x 5".)
Since the collection should not only contain specimens of larger trees but also the wood of the smaller trees and shrubs which is very often beautiful and highly interesting. I have found it practical to choose a size of about 1/2x3x5" for the larger specimens and 3/8x1-1/2x3-1/2" for the small samples of shrubs or for specimens which were not yet obtainable in the proper size. In order to insure interchangeability within the compartments of the collection shelves (see point 6) and to allow arrangement of whatever specimens one wants to display together, the dimensions of each sample should be precise within approximately 1/64". Naturally all sides must be exactly in the square. Such an utmost precision in the all-round dimension would be in vain if the samples were not properly seasoned and absolutely dry. Dry in this sense means that the remaining humidity of the wood specimens corresponds to the average relative air-humidity of the room in which the collection is kept. About 6 to 8% is the usual average for a well heated room. If the samples are worked down to the ultimate size too soon there is not only the danger of shrinkage (undersize) but also the liability of warping, twisting and distortion in general. Consequently subsequent to a preliminary period of drying after felling and sawing the samples should be cut to approximately the final size making an allowance of about 12% in width, 25% in thickness, and 10% in length for shrinkage and distortion. In this case the specimens should be kept in a well-heated room--better still in the same room as the final collection for at least three years before being ultimately finished.
[Note: more information on final drying conditions under Equilibrium Moisture Content (EMC) expectations can be found here...cdr]
5 Ideal surface finish.
This is one of the most important points inasmuch as every kind of artificial finish such as polishing, varnishing, or waxing and the like alters the true color of the wood and since- especially in case of polishing- the structural details of the pores are no longer visible the samples by all means be left without any kind of artificial surface. My own long experience in wood-working has led me to the conclusion that in nearly all cases only a perfectly planed surface will bring out the true beauty of the wood to its best advantage at the same time showing the natural luster peculiar to most spp. of coniferous woods and also to a great many kinds of woods of broad-leaved trees. Naturally the planed surface must be produced by a razor-sharp very finely adjusted plane in the hands of an expert wood-worker. Although it is quite possible to obtain a perfectly even and smooth surface by sandpapering, the natural luster--especially if the sample shows wavy or so-called striped grain-- is usually lost or at least modified. Besides the process of sandpapering tends to round the edges of the pores and partly destroys the crystalline or resinous substance which the pores often contain and the presence of which is sometimes of deciding importance for later determination or comparison. In short all structural details which are of interest to the scientist are best preserved if no sandpaper is used. Unfortunately there are certain woods of great hardness and interlocking grain - such as lignumvitae for instance - as well as certain kinds of burl which do not allow a perfect finish with a plane alone and must be finely finished with the finest sandpaper.
6 Arrangement of specimens.
As mentioned under point 4 a uniform size is recommended in view of an arrangement of the specimens on shelves or in drawers of a collection case.
Such an arrangement not only provides an excellent means of showing a large number of specimens at the same time but also facilitates the manipulation of the samples without danger of damage. A handy drawer should not be much longer than 20" in all and approximately 11" deep. In this case it would contain 12 of the larger specimens. The beauty of the arrangement is greatly enhanced if a small space is left between specimens, in other words, if the drawer is divided into separate compartments for each sample. This is easily done by providing five strips of ply-wood of about 1/16" thicknees in the length of the drawer and one in the width,-- (Here Dr. Mautz shows a drawing which, again, will be difficult to duplicate here. It provides for 12 only specimens laid flat.)
These intermediate strips should be less high than the thickness of the samples which also applies to the rim of the drawer whereas the latter is slightly higher than the strips. I have found it of advantage not to fashion the bottom of the drawer from a ply-wood board but to construct a regular framework. Such a drawer will not only remain absolutely plane and straight but it also allows the samples to be removed for examination without danger of injuring them even in the case they fit rather tight into their compartment.
It is, furthermore, recommendable to choose the size of the smaller samples in such a manner that a certain number will fit into a drawer with the same outside dimensions as provided for the larger specimens. In my own collection 33 small pieces plus the width of the intermediate strips and arranged in three rows correspond to the all-around dimensions to 12 large samples arranged in two rows. This means that the drawers are interchangeable.
The specimens can either be arranged in the order of their botanical relationship or if the collector is more aesthetically than scientifically inclined, in such a manner that the most favorable contrasts are obtained. Another method is the arrangement in certain groups of woods used for similar purposes or resembling each other in respect to their physical properties.
7 Series of woods.
This last point covers a subject to which considerable attention should be given. It is a well known fact, that, for example, the advanced entomologist is not contented with merely one pair of a certain species of butterflies but that he strives to acquire a long series in order to demonstrate the range of variation. As a matter of fact certain variations which occur again from time to time and which are know as "aberrations" have been given a specific name, proving their importance to science. In collections of woods, however, little importance has been attached to the manifold variations of color, structure and figures of grain, which can often be observed within one and the same species. For instance every tree will produce closer grained wood under unfavorable conditions of soil and climate, whereas under the best conditions of growth the space between the annual rings becomes considerably broader. This peculiarity is a well known fact in the wood trade and differences in price and quality are often based exclusively on the spacing of the layers of annual growth. For instance the spruce used in Europe for the finest violins and known here as "tune spruce" is botanically the same species which grows all over central and northern Europe, yet it is quite distinct in structure; the annual rings being only about 1/32" apart and spaced with remarkable regularity. It grows only in certain parts of the Alps and the mountains of Serbia, is very nearly extinct and very expensive.
As far as color-variations are concerned every cabinet-maker knows how different in color the wood of the common walnut can be and how the price can depend on this circumstance. Different color-qualities are known here in Europe by the names of French, Italian, Swiss, German, Turkish and Circassian walnut.
The afore-mentioned variations refer only to the normally grained. However the figure of the grain is subject to a considerably larger range of variation. Unfortunately the great number of possible modulations are known only by different trade-names which are more or less inadequate and are intended, first of all to impress the buyer. Of these names the designation of "bird's-eye-maple" is one of the best since it actually gives an excellent description of the figure of grain. Other expressions are striped, wavy, curly, mottled, blister grain and so on. Furthermore nearly all the trees sometimes produce a growth known as true burl or burr which is an accumulation of latent buds and us usually found at the base of the stem where the roots begin. The structural details of burly-growth are very similar, regardless of the species.
All these varieties are used in finest cabinet-making and inlay work. They are highly valued and commercially available mostly as veneers, hardly ever as solid wood.
Now according to my way of thinking the collector should strive by all means to obtain as many variations of one and the same species of wood as he possibly can. Although the private collector will hardly ever be in position to possess even approximately all the known spp. of wood he can still achieve a collection really worth while and of considerable value if he specializes on a few species and if he can finally demonstrate a complete series of these species with all possible variations of color, structure, and figure of grain.
If it were possible in future times to establish a standard size for the specimens of amateur collections and if numerous collectors all over the world would go in for specialization the time would come when enough material were available to enable the publication of a remarkably thorough and exhaustive book on the woods of the world with illustrations not only of the normal grain but also of the many and beautiful variations. In this case the work of hundreds of amateurs would not only serve for their own satisfaction but be of definite help to science as well, in much the same manner as our present knowledge in the science of entomology has been reached to a considerable extent through the collaboration of numerous private collectors all over the world."