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most garden vegetables exposed to the high temperature and brilliant 
sunshine of the United States. We may reasonably expect that a copious 
supply of liquid manure would enable us to rival the marvellous produc¬ 
tions of California, mentioned in the last Patent Office Report; and I ven¬ 
ture to predict that considerable fortunes ere long will be made by this 
means by market-gardeners residing in the vicinity of large cities, where 
early and superior vegetables command a ready sale at high prices. 
The fluids absorbed by the roots ascend through the woody tissue of 
the stem. It was formerly considered, that the crude sap rises in trees 
exclusively through the alburnum or sap-wood; later observations prove 
that it flows partly through the heart-wood when the tissue is not so 
filled up with secretions as to prevent its passage. As the sap rises in 
the stem it becomes sensibly sweet in many trees, and the specific gravity 
increases. It dissolves in its progress various organizable matters pre¬ 
viously stored up in the tissue, and destined for the nourishment of new 
growths. From the stem the sap flows into the branches, thence into the 
leaves through the veins of the upper surface which are in connectien 
with the wood. In the leaves the sap is exposed to the action of light, 
undergoes certain chemical changes, then passes over the eges of the leaf 
down to the lower set of veins into the bark. The descending, true, or 
elaborated sap, as it has been variously called, descends through the 
vessels of the inner bark to the extremities of the roots, depositing in its 
progress various secretions. A certain portion passes off horizontally 
by means of the medullary rays, which communicate with the centre of 
the wood. 
The direction taken by the radicle or primary root of a germinating 
seed, is considered to be influenced by gravitation ; but the fibrous roots 
appear to be so constituted as to grow most in that direction wherein 
they meet with most food. If we dig a trench, say eighteen inches or 
two feet deep, place in the bottom a layer six inches thick of rich com¬ 
post, then fill up with poor light soil, and sow on the surface, seeds of 
spindle-rooted plants, as carrots or parsnips, the main root will be found 
to go straight down to the rich soil below, which, when the plants are 
taken up in the fall, will be found full of fibrous roots, while very few 
natural fibres will be found in the poor soil above. If the experiment 
is reversed, and the six inch layer of compost is placed on the top of 
