PRACTICAL HINTS 



article, well finished, either polished or not, is nearly always a 

 useful object to examine, but it is the most difficult to understand. 

 To plane a shaving from the transverse section (across grain) 

 of a block of wood, an iron plane, having a screw adjustment 

 to regulate the thickness of the cut, is a most useful tool. 

 It is not necessary to make beautiful sections like those of Hough 

 and Nordlinger. For everyday work sections half an inch 

 wide are amply large enough, and if a number be made at a time 

 a few pieces will be found to exhibit all that is needful. Wood 

 cuts much more sweetly when green than when dry, and 

 moistening will facilitate the work. With woods containing 

 much tannin, ink is produced by the contact of the plane iron, 

 thus spoiling the appearance of the section, so that glycerine 

 should be used with these instead of water. Difficulty will be met 

 with chiefly in three classes of woods, viz., those that are extremely 

 soft and crumble; those that are extremely hard and defy the 

 edge of the plane and the strength of the operator ; and those 

 which, possess rays of a much more delicate texture than the 

 rest of the wood. Sections from the last separate into as many 

 fibres as there aje rays, and need more skill than I have been 

 able to bring to bear upon them. Presumably this accounts for 

 the omission of most of these woods from Nordlinger' s series, 

 for he must have been in possession of some, as they were com- 

 monly employed in Germany during his lifetime. Sapwood is 

 always easier to cut cleanly than heartwood, and wherever pos- 

 sible a portion of it should be included in the section. In one 

 of the Ebonies (Diospyros melanoxylon) the heartwood is almost 

 impossible to deal with, but the sapwood cuts very sweetly indeed. 

 Nordlinger's section is from the sapwood. and is a little misleading 

 unless the reason be well understood. In a collection of solid 

 specimens, many will be found full of fine cracks at each end ; 

 and to obtain large sections it will be necessary to cut away the 

 wood until a compact surface is reached, a proceeding which 

 entails a greater sacrifice than a large section is worth, as the 

 small pieces between the cracks may be sufficient for all purposes. 

 After cutting the section, which will leave the plane as a curly 

 shaving, it should be placed upon a piece of glass and the free 

 end moistened, water being gradually added as the section 

 uncurls, as it will usually do unless it be wetted too suddenly. 

 It may require assistance, but these matters suggest their own 

 remedy. After moistening, it should be pressed in blotting- 

 paper for a moment, the paper changed and put away for 

 a while under slight pressure. The subsequent treatment 

 may consist merely of laying between glass slips, or simply 

 between papers, as Nordlinger does. For exhibition pur- 

 poses or for photographing the section may be mounted in 



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