PRACTICAL HINTS 



Durability and other serviceable qualities, which make 

 wood commercially valuable, are not altogether germane to our 

 subject, as they cannot be employed to identify timber ; hence 

 the reader is advised to consult other works if information be 

 desired upon these points. Inasmuch, however, as they are 

 useful facts and take up little space, a few lines have been 

 devoted to them in the descriptive part of this book, especially 

 in the case of the Colonial woods. Much time has been devoted 

 to the compilation of the opinions of various observers in the 

 hope that little known Colonial timbers may be tried, and that 

 such trials may not be attempted blindfold. 



Details of elasticity, breaking-strain, fuel-value, resistance 

 to impact, etc., must also be sought elsewhere. The list of 

 works consulted, given at the end of the book, may be of service 

 in guiding the reader to this class of information. 



For the purpose of discrimination the solid wood should be 

 taken and all the information which it will afford considered first. 

 There is nothing like the examination of the solid wood, for in 

 it can be seen the structure undisturbed and the mutual relation 

 of its parts. Thin sections are of great value, but when all 

 is said the information they yield, over and above that which 

 can be seen in the solid, is limited to one or two details. 

 A thin section shows the relation of the elements in merely one 

 plane, and to build up an image of a cube of wood from thin sec- 

 tions from three sides requires a considerable effort of mind, 

 and the conclusion is generally false. This is the case when the 

 cross section is cut accurately with its surface precisely at right 

 angles to the vertical axis of the tree, but if it be in the least out 

 of truth it can be absolutely misleading, for all the round orifices 

 of the pores become oval and the rays become shortened and broad- 

 ened. With the solid wood, on the other hand, an examination 

 of all sides readily disposes of all ambiguity, as any inaccuracy 

 of the cutting declares itself. Furthermore the thin section 

 shows but one or two layers of cells separated from the sub- 

 jacent layers which have a definite and important relation to 

 them. This can, in most instances, be seen in the solid wood, 

 as it is to a certain extent transparent. 



The first precaution is to obtain a perfectly smooth surface 

 upon the wood by means of a plane or knife. The blade must 

 be very sharp, for the surface obtained by a dull blade has a quite 

 different appearance. A polished surface is frequently 

 sufficient to show all detail, and every piece of furniture 

 should be overhauled in search of information, but it must 

 never be forgotten that a part of the polishing process consists 

 in filling up the pores with powdered pumice-stone, so that 

 they appear to contain a light-coloured secretion. A turned 



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