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Show I., .. I -... -. .. ~.. . 302 SPRING ACTION. the first year, the wood and bark were not begun, and the vegetable action is confined to a mere point. Still the exciting of the former oak, so that it shall pro~nc.e the new one, is a very wonderful matter; nor 1s.1t easy to understand how, or possible to tell why, .1t takes place. The cause is beyond human scrutmy, but the mode is well worthy of observab0n. When the return of the genial season has brought the tree to a certain degree of heat, it begins to act; and the longer that the tree stands in the autumn before its ripening of wood is completed, and the leaves are shaken off, the longer must the spring in general advance before the part of the tree above ground comes into action. There are exceptions to that, but they are characters only of peculiar species T11e underground action begins first, and rootlets, which have the same period of action as the leaves, though it begins and ends sooner, are formed to a considerable extent before the tree itself shows any signs of reviving. The rootlets of the form er year are not cast off like the leaves, but are converted into "root wood," which, from the circumstance of its beil)g covered from the light, does not contain so much charcoal as the stem and branches. The sap ascends through the vessels of the wood, and in all probability dissolves the peculiar matter which is in the cells, and takes it into the current; for that matter is soluble in water, and as there is less and less of it in the wood as that gets older, it is probable that it is a sort of store prepared towards the end of each season, to assist in the action at the begin-ning of the next. As the spring action begins in the lower part of the tree, if any part of the trunk offers more resistance than another, from the bark being tightened or what is called hide-bound, or any other cause, the tree, if it be of a species which puts out late.ral buds, is apt to throw out suckers at the roots, or new shoots on the stem and lar~e branches, and these very much PROGRESS OF VEGETATION. 303 Tinhjuersee baoreth v tehre gar otw toth aa nd appearan?e of the trees. deed on all t!eef that Pfr:ar ol~· frmt trees, and innatural habits. But when th~u Iva.ted ~n~t of their has every chance of bein . tree Is l:lllll1Jured, as it first year, the whole tree g m a seedlmg oak of the ~he buds are expanded int~oon comes into action; mto twigs. After the tre ~eaves, and lengthened thence ti11 the leaves ba e as. begun t.o act, and the jt~ice or sap of the tr:: fstt.am~d theu full size, bark Is comparative! d m t e wood, and the ~ave attained their fuh s{fe· ~ut a~ter the leaves bon, sap appears in the b' tn are m complete acThe sap which then a ar a.s well as the wood. same as that which w ppe~rs IS not however the leav:es came on Th ~s m the wood before the had ~i'h influenc~ u o e ~Ir? heat, and light have all for· the' compositio~ 6~ tiht m the lbeaves, and fitted it In the e new su stance pared they~:~~ :~os~~' those that Jlave . been prewas in the first oak . b~~h.e ~~ocess Is the same as it pared jui~e SJ?reads itself I~et.:e~~h:~ parts, the prebark. First m a state n 1 . e wood and the becomes a little granula:a[hY fl';{g' but it gr~dually matelydivides into wood a~d b~\. rous, and It ultias that of the former ea . ar m the same manner completely performe/ th r 'I and when that has been and the tree asses · ' ~ eaves are " healed off" result of thep annua~n~o /ts repose as before. The former tree, roots, and ~l{o~it~as been to case the and bark, and to lengthen' .t b a ne'Y' layer of wood If we could by an mean I y a twig at every bud. pulling the first oJt of th~ separate the t~o trees by iS pulled out of its cas _sec~nd, as an mstrument two years' progress of ~h we s ould have a sight of would be wanting tog· e oa~, and only the leaves grown from the acorn ~:e .us \he whole of what had The third and eve rmg .ose years. repetition of what to;[ slccededu:g year is merely a p ace urmg the second, only |