34 Mississippi Valley Horticultural Society. 



Again: It is in the cells and woody tubes of the alburnum (sap-ivood) that 

 the fluid absorbed by the roots is transmitted to the opposite extremity 

 of the stem, and these cells communicate with those of the leaves, which 

 receive it from them. In the bark the woody tissue has a somewhat dif- 

 ferent form. Instead of the tubes (cells) lying side by side (as in the sap- 

 wood), they branch horizontally from each other, and their function is that 

 of conveying back from the leaves the juices of the plant which have been 

 there elaborated out of the sap brought up by the vessels of the sap-wood." 

 Thus they explained the theory called the descent of the sap. 



The study of the grand text-book of Nature for the past lifty years has led 

 us to believe that these theories, which we have quoted, have no foundation 

 in. fact. We, who are practical horticulturists, have often noticed those 

 large protuberances close to and over the union between the scion and 

 the stalk when we grafted the pear on the quince, the apple on the wild crab 

 and the Heart varieties of the cherry upon the Morello stalk, producing in 

 a few years larger protuberances than a cord would if tied tightly around the 

 trunk of a healthy young exogen. Again, the amount of sap passing through 

 the small cells of the bark must be very small, compared with the amount 

 that passes through the sap-wood and cambium layer, in a season favorable 

 to wood growth, when the tree adds one or two inches of solid woody matter 

 to its diameter. Every observant mind who has made this delightful sci- 

 ence a close study in the grove or orchard, must have received <ib extra reve- 

 lations from Nature, which are not imparted to the scientist in his cabinet, 

 and which the text-books do not nor can not give. 



Permit us to present a few illustrations in support of the theory that the 

 sap does not descend, but is elaborated, retained, spread, ripened and com- 

 pressed over the entire inner surface of the tree during its upward tlow. 



In the year 1832 we had charge of a large conservatory for the growth of 

 palms, orchids, cacti, and other tropical plants. In front, planted in a rich 

 artificial border, outside of the walls, grew twelve grape-vines of the Black 

 Hamburg variety, one vine opposite each rafter; age of vines, twenty years; 

 height of stems, three feet. At this point they branched into two limbs, 

 each thirty feet long; one limb of each vine was introduced inside the house 

 and trained up the rafter early in the month of February; the other limbs 

 were trained upon a trellis outside of the glass roof, up the middle of the 

 sash. The limbs inside, exposed to the regular heat of 70^, soon began to 

 push their buds, expand their leivos, unfold their blossoms, and large 

 bunches of ripening berries hung down from the rafters, while those limbs 

 outside were just beginning to show signs of active life. The ripe clusters 

 were all gathered, the new wood and new buds all ripened and matured, 

 the leaves had performed their functions, and, sere and yellow, were begin- 

 ning to fall from the vines inside, while the vines on the roof outside were 

 making a vigorous and luxuriant growth, (iuery: How did the tlescending 

 sap from the limln inside liow down that three feet of stem, througli which 

 was rushing a resistless upw ird How of sap towards the vigorous growing 



