the little out-let, and if it enters the fkin, caufes pain and inflammation by the pungency of its falts. The leaves of plants are of great confequence to their life.. At thefe, the air paffes in, and goes through the whole plant, and out again at the roots. If the leaves have no air, the plant will die, as is eafily proved by the air-pump: whereas if the leaves be left on the outfide of the receiver (parted by a hole cemented with wax) while thefe have air, the plant' will thrive and grow, though its roots and ftalks are kept in vacuo. The leaves likewife chiefly perform the neceffary" work, (but who can explain the manner!) of altering the water received at the roots, into the nature of the juices of the plant. And hence it is, that the life of plants depends fo immediately upon their leaves. The husbandman often fuffers, for want of this knowledge. A crop of Saint-foin is valuable; and its roots being perennial, will yield an increafe for many years. But it is often deftroyed at firft, by fuffering it to be fed upon by fheep. For if they eat up all the leaves, the root cannot be fupplied with air, and fo the whole perifles. Leaves being forneceffary to all perennial plants, a reverfionary flock of them is provided.. The leaves of thefe plants are always formed in Autuan, though not unfolded till the fol lowing Spring. They then open and increafe in proportion to the motion of the fap, and the quantity of nouifhment the plant receives. Thefe leaves alfo, though not yet appearing out of the bud, may fuffice for the extremely fall motion, which the fep of thofe perennial plants, that drop their leaves, has in winter. But befides thefe Autumnal leaves, there is another fet formed in Spring and expanding till Midfummer. Thefe are of infinite fervice to many fort of trees, particularly to the malberry, as they fave its life, when the first fet of leaves have been all eaten up by the filk-worms. The analogy between the parts of plants and thofe of animals may now more fully appear. The parts of plants are, 1. The 1. The root, composed of absorbent vessels, analogous to the lacteals in animals: indeed performing the office of all thofe parts of the abdomen, that minifter to nutrition: 2. The wood, compofed of the capillary tubes running parallel from the roots, although the apertures of them are commonly too minute to be feen.. Through thefe, which are analogous to arteries, the fap afcends from the root to the top: 3. Thofe larger veffels, which are analogous to veins. Through thefe it defcends from the top to the root. 4. The bark, which communicates with the pith by little ftrings, paffing between the arteries. 5. The pith, confifting of transparent globules, like the bubbles that compofe froth. The fap enters the plant in the form of pure water, and the nearer the root, the more it retains of that nature. The farther it goes, the more it partakes of the nature of the Plant. In the trunk and branches it remains acid. In the buds it is more concocted. It is farther prepared in the leaves (as blood in the lungs) which being expofed to the alternate action of heat by day, and cold by night, are alternately dilated and contracted. Is not then the motion of the Sap in plants (like that of the blood in animals) produced chiefly by the action of the air? All plants have the two orders of velfels, 1. Thofe which convey the nutritious juices. 2. Air-veffels, hollow tubes, within which all the other veffels are contained. Now the leaft heat rarefies the air in thefe air-velfels, thereby dilating them, and fo caufing a perpetual spring, which promotes the circulation of the juices. For by the expansion of the air-veffels, the fap veffels are preffed, and the fap continually propelled. By the fame propulfion it is comminuted more and more, and so fitted to enter finer and finer veffels; while the thicker part is de pofited in the lateral cells of the bark, to defend the plant from cold, and other injuries. Thus is every plant afted on by heat in the day-time, efpecially in fommer; the fap protruded, then evacuated, and then then exhaufted. In the night the air-veffels being contracted by the cold, the fap-vessels are relaxed, and disposed to receive fresh food, for the next day's digeftion. And thus plants do,, as it were, eat and drink during the night-feafon. [To be continued.] A Letter from HOWEL HARRIS, to JOHN CENNICK. Dear Brother, Brinkworth, October 7, 1741. HAT have we to do, but, to fuch as never believed, WH to fhew them the abfolute neceflity of Faith? and to fuch as have it, the neceffity of keeping it in continual exercife. While we are looking to Chrift, we become more like him, and confequently bear more fruit to his glory. I find that while the eye of my foul is fixed on him, I am not lead away by the defire of the eye, the defire of the flesh, or the pride of life; but all things move regularly within. To have the law of God fo written on my confcience, as to check me for my firft wandering, to have the Spirit ever prefent, to put me in mind of my own helplessness, and having my shield on, fo as to be able to repel Satan's darts; then that mind, fpirit, temper, love and meekness that was in Chrift, and the fruit thereof in my life, is a sweet smelling favour to the Lord. O how fweet is this living in the fight of Jefus! Pray for me that I may know it more and more; that I may never reft till I am made quite paffive and refigned under the Saviour's hand receiving all from him, and laying out all for him. Being dead to felf, and living to him, feeking and admiring him, lying at his fees, having Unbelief and Satan bruifed under my feet: Chrift reigning King in Sion, continually fhewing me his love, righteoufnefs and power; having circum cifed cifed my heart, and removed the ftone out of my flefh, giving me a tender, loving fympathizing heart, fetting the Spirit within me, keeping me in the dull, bringing his words to my remembrance, comforting me, leading me, enlightening me, ftrengthening me, affifting me; being now continually at a well of water in me fpringing up into everlafting life; keeping under, and mortifying every firing of the body of fin, by applying the fin-killing, as well as the fin-forgiving blood: triumphing over all his enemies as Captain of our falvation, making whole the fick, as Phyfician, taking away the fcales from our eyes, enabling us to understand as a Prophet: this glorifying of Chrift in all his offices, names and relations; and preaching all the promifes, and infifting on it that our fanctification is as much the will of God as our juffification; and that he commands us to be holy as well as to believe, and that Chrift died to deftroy the works of the devil, and to bruife him and caft him out, as well as to make our peace with God; to redeem us from the power and dominion of our original, as well as our actual fins: this, I fay, is fuch a doctrine as will fir up all the powers of hell indeed against us. When you declare that all idols must be taken away, and that there is no allowance to spend our time or our money, on the defire of the eye, the defire of the fleth, or the pride of life; and that we must not follow our own will in any thing, no not fo much as to drefs according to the world, nor to speak idle words fometimes! nor to be now and then in a paffion, nor to lay up treafure on earth against old age; but must trust Christ with foul and body, working with our hands that we may have not to hoard up to help us when weak; but) to give to those that need it; feeking firft the kingdom of God and his righteoufnefs, relying on that promife, All these things shall be added unto your and that we must not only have the love of God once, but muft abide in his love, and if we do not live a life of fruitfulness, a life hid with Chrift in God, God, we are only fruitless branches, and must expect to be cut off; if we are content with taftes of Chrift, without living on him and to him: when, I fay, we fhall have power to declare that Chrift must have all, we fhall have many cry out, This is a hard faying, who can bear it! Calliftus. POOR Sebastian! I really pity the unhappy youth ! Sophronius. Perhaps this was the most fortunate incident in his life. As he was in danger from his extreme vivacity, this disappointment gave a check to it. Affliction is often our best friend, whofe awful leffons are never fo neceffary as in youth: we are apt to fet out in life, ardent in the pursuit of happiness, and fanguine in the hopes of attaining it; but we generally go upon a wrong fcent; we feek for it among diversions and fenfual pleafures, where it is not to be found; happy they who are called off by affliction, and thrown into the right courfe. Sebaftian fet out the next day for the University. The cheerful fociety of the place, and the natural propensity of youthful minds to joy, foon enabled him to recover his peace. I did not fee him again, till above a year afterwards, when he came and afked our pardon for the uneafinefs he had given us. He is now our worthy Rector, is himself married, and his and his wife's agreeable converfation has once more. . VOL. IX, 4 F renewed |