habits, as well as by their sensibility to heat:  for the roots of potatoes, onions, &c. will germinate with much less heat in the spring than in the autumn; as is easily observable where these roots are stored for use; and hence malt is best made in the spring. 2d.  The grains and roots brought from more southern latitudes germinate here sooner than those which are brought from more northern ones, owing to their acquired habits.  Fordyce on Agriculture. 3d.  It was observed by one of the scholars of Linneus, that the apple-trees sent from hence to New England blossomed for a few years too early for that climate, and bore no fruit; but afterwards learnt to accommodate themselves to their new situation.  (Kalm’s Travels.) 4th.  The parts of animals become more sensible to heat after having been previously exposed to cold, as our hands glow on coming into the house after having held snow in them; this seems to happen to vegetables; for vines in grape-houses, which have been exposed to the winter’s cold, will become forwarder and more vigorous than those which have been kept during the winter in the house. (Kenedy on Gardening.) This accounts for the very rapid vegetation in the northern latitudes after the solution of the snows.

The increase of the irritability of plants in respect to heat, after having been previously exposed to cold, is further illustrated by an experiment of Dr. Walker’s.  He cut apertures into a birch-tree at different heights; and on the 26th of March some of these apertures bled, or oozed with the sap-juice, when the thermometer was at 39; which same apertures did not bleed on the 13th of March, when the thermometer was at 44.  The reason of this I apprehend was, because on the night of the 25th the thermometer was as low as 34; whereas on the night of the 12th it was at 41; though the ingenious author ascribes it to another cause.  Trans. of Royal Soc. of Edinburgh, v. 1. p. 19.]

        “Breathe, gentle AIR! from cherub-lips impart
        Thy balmy influence to my anguish’d heart;
325 Thou, whose soft voice calls forth the tender blooms,
        Whose pencil paints them, and whose breath perfumes;
        O chase the Fiend of Frost, with leaden mace
        Who seals in death-like sleep my hapless race;
        Melt his hard heart, release his iron hand,
330 And give my ivory petals to expand. 
        So may each bud, that decks the brow of spring,
        Shed all its incense on thy wafting wing!”—­

        To her fond prayer propitious Zephyr yields,
        Sweeps on his sliding shell through azure fields,
335 O’er her fair mansion waves his whispering wand,
        And gives her ivory petals to expand;
        Gives with new life her filial train to rise,
        And hail with kindling smiles the genial skies. 
        So shines the Nymph in beauty’s blushing pride,
340 When Zephyr wafts her deep calash aside;
        Tears with rude kiss her bosom’s gauzy veil,
        And flings the fluttering kerchief to the gale. 
        So bright, the folding canopy undrawn,
        Glides the gilt Landau o’er the velvet lawn,