M. Downing - You have desired information respecting the effects of the late severe winter upon various orders of vegetation in different parts of the country, and as I think the suggestion a most valuable one, I send you a contribution tenoning our locality.

Portland is in north latitude 43°, 39', 52"; west longitude 70°, 13' 34", and 542 miles north-east from Washington. The last winter was one of the most severe we have had for many years; in December the mercury in Fahrenheit's thermometer fell on the 10th to 10° below aero, and averaged for the month from 10° below to 40 above aero, and on five different days it fell below aero, via: on the first to 6° below - 2d, 1° - 10th, 10o - 11th 6° - 14th, 3°. The average temperature was nine degrees colder than in December, 1850, and the coldest month for the last 31 years, except that in 1831 and in 1835. In January the mercury fell below aero on six different days, via: on the 16th, 10° - 17th, 1° - 18th, 4° - 19th, 4° - 20th, 16° - 22d, 7o. The average temperature for the month was 17i°, being two degrees colder than the average for the last 37 years. In February the mercury fell below aero on three different days, via: on the 19th, to 8° - 20th, 7° - 21st, 3°, the average temperature for the month being 23 degrees, by three observations a day, and two degrees warmer than the general average for the last' 32 years; the range being from 8° below, to 42° above aero.

The average for the three winter months was 19°, being three degrees colder than the general average for the last 32 years, and aa cold as any winter since 1820. The thermometer was noted at sunrise, noon, and 8 P. M. During the last 37 years, the lowest points in the months of January, at which it has been registered at this place, are as follows, via:

1891................. 16deg.

1829,................13

1897,................ 13

1830.................18

1833,................ 15deg.

1835,............... 18

1839,............... 16

1844................. 14

1848,................ 14deg.

1851,...............16

1852.................10

For every one of the 37 years, the mercury in January fell below aero, varying from one to eighteen degrees, except the years 1825 and 1841.

Under the influence of this severe winter, which lingered for into the lap of spring, and from the sad forebodings expressed in various quarters, we had reason to expect a desolate account from our shrubs and fruit trees; but to our agreeable surprise, all our fruit trees, earlier than usual, began to exhibit signs of vitality, and are now covered with bloom. I have now on my grounds in full blossom, of Pears, the Bartlett, the good Louise of Jersey, the Vicar of Winkfield, the Melting Autumn, (Ftmdante d'dutomru,) Duchess of Angouleme, Summer Dean, (Doyenne d'Ete,) Ac.; of Cherries, the Flesh Colored Bigar-reau, the Honey, and several of the hearts; of Plums, Smith's Orleans, Prince's Gage, Green Gage, and several others; they promise fine crops - never looked better, and are a few days earlier than the usual time for blossoming. Of a doaen budded French roses, imported last spring, including the Giant of Battles, Persian Yellow, and several mosses, I did not lose one, although they were not protected, except by a thick covering of coarse manure about their roots; a fine Isabella grape, and several Sweet Water's against a brick wall, with no other covering than this manure about the roots, bore the season remarkably well, and are now starting out strongly, and in good health, and with a prospect of the usual crop.

I never lay down or cover my grape-vines, and have never experienced any inconvenience or loss from this neglect, the Tines usually bearing well, being trained to brick walls facing south-east and south-west, in the open air. My Osage Orange hedge does not appear to have suffered in the least, and is now putting out its buds. I planted the seeds of this hedge in the spring of 1849, and it is now in a flourishing condition; about six inches of the extremities is killed every winter, but the growth exceeds this every season, and it is now more than three feet high, thick, and well set. A plant of the Weigela Rosea, which I set out last spring, did not suffer in the least, although it was unprotected, except about the roots; it is now alive, and pushing out its foliage, even to the extremities. Nor did the peach tree suffer; I have one now full of blossoms, and promising well, and also an Apricot, although we make no calculation on either of these kinds of fruit, seldom haying any ripen here; owing as much, perhaps, to our vicinity to the sea, and the prevalence of sea winds during the summer, as to our latitude.

We are more than half the compass open to the sea, from the north-east to the south-west, and the sea winds come in from the south nearly every day of summer, except when it is varied by the still cooler breeze of the east. We do not here exclaim with the poet, " 0, for a bee-ker full of the warm south, the true, the blissful hypocrene." Our warmest wind in spring and summer is the due west.

I have been surprised, and perhaps it will surprise you, to perceive, on a comparison of the seasons for a century and a quarter back, which I am able to do from the journals of our two earliest clergymen, Smith and Deans, the great regularity and uniformity which have attended the opening and blossoming season of the year. Deane, our venerable pastor for fifty years, was the author of the first work on agriculture published in this country, styled " The New-England Farmer, or Georgical Dictionary," published in 1790; a new edition of which, with modern improvement, was issued a few years ago, under the supervision of Mr. Fessenden, editor of the "New-England Farmer," an able and popular periodical.

It is a common impression that the seasons have undergone some change within the past century - and that whether from improved cultivation, or change in climate, or other un-definable cause, they are earlier now, and more genial than formerly. This is a mistake; for by recurrence to our ancient records, we do not find that the pear, the plum, or the cherry put forth their beautiful blossoms any earlier, or any different among us now, than they did when our city was but a poor fishing village, straggling along on the margin of Casco river on one side, and skirted by the forest on the other. The progress of wealth and refinement have had no effect on them.