263 Of the Wood of f rees,, 
vefiels length-ways, H H is the cavity of one of the great 
vefiels* being full of turpentine threads, or little tubes, 
with black fpots curioufly wove together $ as at fig. 499. 
Fig. 500. is a final! and thin piece of beach, cut tranf- 
verlly, and fig. 501. reprefents the fame as it appeared in 
the microfcope. Its length between A B and D C is the 
breadth of a circle of one year’s growth. The perpen¬ 
dicular vefiels in this wood are of two, the horizontal 
ones of three fizes; of which thofe exprefied by E E, 
fig. 501. are exceeding fmall; in the upright fedfion, fig. 
502. thefe horizontal vefiels are cut tranfverfly, and {hewn 
by H H, the fecond fort of horizontal vefiels are feen 
lengthwife, from D to A, fig. 501. and a tranfverfe 
fedfion of the fame vefiels are feen in the upright 
fedfion of the timber, fig. 502. at I, I, I, and at KK 
are feen the great perpendicular vefiels. 
Fig. 509. reprefents a tranfverfe fedfion of a fmall bit 
©f black ebony, greatly magnified, of which G, G, G, 
are the large upright vefiels. K K, in fig. 510. fhews 
one of thefe large vefiels cut lengthwife, and at fig. 511. 
is feen another of a larger fort, in which are many 
ftreaks and fpots. The fecond fort of perpendicular vefiels 
are feen between A B, A B, and the third fort between 
CD, CD; a fourth fort are fquarirh, and included be¬ 
tween the fecond and third in the upright fedfion, fig. 
510. L L {hews the finallefi: vefiels, and I, I, the tranf- 
verfe fedtions of the horizontal ones. 
Fig. 503. AB CD is a fmall piece of box, cut tranf¬ 
verfly, and of the fame fize to the naked eye as the piece 
of ebony. This wood alfo confifts of large and fmall 
perpendicular vefiels intermixed; the large ones are com- 
pofed of fidns, and are full of extremely minute particles, 
as may be feen in the upright fedlion thereof at E E, fig. 
304. the cavities of the lefier veffels are fhewn lengthways 
at 
