44 



NEW ENGLAND FARMER. 



Jan. 



impossible to avoid the loss of one-fourth of the heat 

 generated, in combination with water, in steam and 

 vapor. Most of the heat rendered latent in these 

 gaseous bodies passes up chimeney, where they are 

 condensed, and give out their heat to warm all out 

 doors. 



We are anxious to give the most unscientific reader 

 a clear idea of this subject, for it is really one of 

 great practical importance. Look at it, then, in 

 this light : You have divided your 100 lbs. of green 

 oak, beech, or maple wood, into 65 lbs. of dry com- 

 bustible matter, and 35 lbs. of cold water. Every 

 pound of this water you evaporate in green wood, 

 and throw the hPMt away by the consumption of a 

 part of your 65 lbs. of fuel, and then take the heat 

 evolved by the balance of your fuel to warm your 

 room. How many ounces of perfectly dry wood 

 are required to transform a pound of water into 

 steam, we cannot at this moment say; nor can 

 we determine what portion of the heat taken up by 

 steam in the combustion of green wood is again 

 evolved by condensing in the room where the fire 

 is made. We believe, however, that the usual loss 

 is about equal to one-third of all the heat contained 

 in 65 Iba. of kiln-dried wood; and that the gain in 

 seasoning wood under cover is at least 25 per cent. ' ' 



For the New England Farmer. 

 HISTORY OF VEGETATION—NO. 2. 



Tn accordance with my design at a former writ- 

 ing, I now purpose to follow out briefl:y some of 

 the more important changes which take place in 

 the process of vegetation,after the plant has become 

 fully developed. 



Vegetable economy — so to speak, is a subject 

 fraught with a considerable interest ; especially 

 when we consider the close analogy there is be- 

 tween the vegetable and the animal kingdom. But 

 yet how many there are of us, even, who have 

 been "brought up in the woods," with plants for 

 our almost constant companions, who can hardly 

 recognize in a tree an organic thing ? Nay, how 

 many who are entirely ignorant of its internal 

 economy, or the various "ways and means" by 

 which it attains to its gigantic proportions. It 

 has been said, and truly, that nature was like unto 

 a great book, always spread out before us — always 

 replete with instruction; yet while it is the high 

 privilege of the farmer to be ever under her im- 

 mediate guardianship, to hold daily communion 

 with her "visible forms," of what avail is it, in- 

 deed, if her "various language" be to him, after 

 all, a dead letter. Of what avail is it, we say, if 

 there are "sermons in stones" or "books in the 

 babbling brooks," if they are written in a language 

 whicli he will not take pains to understand. We 

 often spend years over some antiquated product of 

 ancient lore, or conning some critic's 



" articles 



On Hebraic points and the force of Greel; particles," 



yet with how little zeal do we employ the means 

 within our reach for gathering up those lessons of 

 wisdom, written "in the stones" on the blade of 

 grass, or in "the babbling brooks," orwhich are 

 made so strikingly manifest in the history and 

 economy of that most common product of nature 

 — a tree. But to proceed more directly with our 

 thesis. 



First. The hark, like the skin of the human body. 



is composed of three distinct coats, the epidermis, 

 the paranchyma and the cortical layers. The epi- 

 dermis is the external covering of the plant ; it is a 

 thin transparent membrane, and is either silicious 

 or resinous in its nature. In those plants noted 

 for strength or hardness, the epidermis is almost 

 entirely silicious, while in the opposite variety, it 

 is resinous. The design in thus uniting materials 

 of this character in the composition of the outer 

 covering of the plant must be obvious. The hard- 

 ness of the one and the resin from its want of affi- 

 nity for water, in the other, preserves the plants 

 from the destructive effects of violent rains, severe 

 climates, or inclement seasons. 



The paranchyma is immediately beneath the 

 epidermis ; it is that green rind which appears 

 when we strip a branch from a tree or a shrub 

 from its external covering. It also forms the green 

 matter of the leaves and is composed of tubes filled 

 with a peculiar juice. This juice, it may be well 

 to say in this connexion, differs much in its nature 

 in different species of vegetables. For instance, it is 

 sometimes saccharine, as in the sugar-cane, some- 

 times resinous as in'firs and evergreens, sometimes 

 of a milky appearance, as in the laurel. In break- 

 ing a young shoot, or in bruising a leaf of laurel, 

 we shall observe this piece to ooze out in great 

 abundance. And it is by making incisions in the 

 birk, that pitch, tav and turpentine, are obtained 

 from firs and pines. And, by the way, the well 

 known durability of this species of wood is chiefly 

 owing to the resinous.nature of its peculiar juices. 

 With regard to the chief use of these juices, it is 

 supposed that it is from these that the plant more 

 immediately derives its nourishment. 



The cortical layers are immediately in contact 

 with the wood, and consist of small vessels through 

 which the sap descends after having been elabora- 

 ted in the leaves. The cortical layers are annual- 

 ly renewed, the old bark being converted into 

 wood. Immediately beneath the cortical layers, 

 then, is the alburnum or wood, through whose 

 tubes the sap ascends. The wood is composed of 

 woody-fibres,mucilage and resin. They are disposed 

 in two ways, longitudinally and concentric. The 

 former is called the silver-grain of the wood, and 

 the latter the spurious grain. These last disposed 

 in layers from the number of which the age of the 

 tree may be computed, a new one being produced 

 annually by the conversion of the bark into wood 

 The oldest and most internal part of the alburnum 

 is called heart-ivood. It appears to be dead, at 

 least no vital function, are discernible in it. It is 

 through the tubes of the living alburnum that the 

 sap rises. These, therefore, spread into the leaves 

 and there communicate with the extremities of the 

 cortical layers, into which they pour their con- 

 tents. 



Now, if we have done with the anatomy of the 

 plant, we will treat a little more particularly upon 

 that which constitutes its "life-current" and which 

 amounts almost to a circulation. 



First. The sap, evidently composed of water 

 absorbed by the roots, and, like the blood in 

 the human system, holding in solution the va- 

 rious principles which are to contribute to the 

 nourishment and support of the living thing, as- 

 cends through the tubes of the alburnum into the 

 stem, and thence branches out to every extremity 

 of the plant, where it is elaborated by the leaves, 

 (by which operation its super-abundant fluid is 



