Need we mention, that it is only in the cases where the partial death or decay has resulted from casualty, or something not connected with the general system of the plant, or with the soil, or other external circumstances (unless these can be changed), that renovation by clearing away the decayed or sickly parts is attainable? Where the plant is sinking from mere old age, a source of decay of which in some kinds at least we have doubts, or from the soil being improper or exhausted for the particular kind of plant by long occupancy, or from any circumstance not admitting of remedy, the attempt to heal up the wounds caused by cutting out the diseased parts, or to induce new vigour by cropping the top, must be abortive, or only attended with partial or temporary success. Our author, who is a practical man, apparently very little disposed to throw away time upon inquiring into causes, does not attempt even to guess at {196} the mode by which his composition performs the wonders for which he gives it credit. It is impossible, by any salve, to promote discharge from the bare alburnum, though cut into the vital part, to form, or assist in the formation, of bark; and the sum of the resulting advantages consists in preventing the vitality from becoming extinct far inward from the section (as under the best management to a certain extent it will become so), by an antiseptic cover from the drought and moisture, heat and cold; in promoting the spread of the juices from the edge of the bark over the bared part by exclusion of drought, and by forming a defence against insects. We have found a paste of pure clay, wrought up with some fibrous matter, as chaff or short hay, an excellent cover for tree wounds, applied in spring or early summer, when dry weather followed the application; but in autumn or winter, and when moist weather followed, the clay, by remaining wet, only served to induce corruption. We think this clay paste (probably benefited by a powdering of charcoal on the inside) the best application when applied in spring. We have seen a terminal cross section, of about one inch diameter, of a long branch, covered quite over in two months with bark when clayed; and a tree of three inches in diameter, from {197} which a dog had torn off the bark from one half of the circumference of the stem, entirely renew the lost bark in one season, when immediately clayed over. Resins, oils, bitumen, paints and composts without number, have been used with more or less success, depending upon the period of the year, weather, kind of tree, individual health, and other circumstances; but these salves should, as in flesh-wound salves, be considered only as protections, or slightly auxiliary to the restorative energy of nature, not as cures. {198} V.—MR WITHERS.