light of thy holy spirit, to guide us on our way; to enable us rightly to direct that knowledge we are enabled to acquire, and never to mistake or pervert those abilities with which we have been blessed, on the proper or improper use of which depends our future misery or felicity! MARCH XVIII.; The Utility of the Vegetables. If we consider the great number and diversified appearance of vegetables, we shall perceive, as in every thing else, the beneficent designs of the Creator. What other end could he have in view in covering the earth with so many different herbs, plants, and fruits, than the advantage and felicity of his creatures? Such is the number and variety of plants, that upwards of 30,000 species have already been enumerated; and every day more are added to the list. Their increase seems infinite: who, for example, is not astonished. when he is told that one single grain of maize (Indian wheat) produces 2000 more; that one poppy-seed multiplies itself so, that, in two or three years, it produces sufficient to sow a large field? Hence, no one can doubt the care of Providence, particularly when they consider the use that has been made of vegetables from the earliest ages. Do not fruits and vegetables daily furnish us with the most salubrious and nourishing aliment? And are we not indebted to the vegetable kingdom for the greater part of our clothing, furniture, and habitations? Every part of a plant is of some utility. The roots afford us food, medicines, pitch, dyes, and various utensils. With the wood we construct our buildings, furniture, and different instruments, machines, &c.; it likewise serves us for fuel, and from it we procure charcoal and medicines. The bark is of particular use in tanning, as well as in the cure of some diseases. The ashes are useful in fertilizing and ameliorating the soil, bleaching cloth, and making saltpetre. The resin is used in painting, and enters into the composition of pitch, tar, and balsams. Turpentine is used, as a medicament, and colophonia (hard resip) to varnish, to solder, and to rub the strings of musical instruments; and mastic is used in perfumes. Flowers, delightful both for their beauty and fragrance, are very useful in medicines, and supply the bees with their wax and honey. Fruits are singularly beneficial and grateful, whether fresh from the trees, boiled, dried, or preserved. But it is not man alone which receives advantage from the vegetable kingdom; the greater part of animals derive their nourishment from that source. For this purpose we find fields and meadows innumerable, covered with every variety of plants and vegetables. The wants of every individual are provided for; each knows the kind of vegetables most suited to its nature; and no one can number the blessings afforded by this kingdom, nor find expressions to celebrate the goodness of God. MARCH XIX. Structure of the Human Heart. How wonderfully and exquisitely formed is that muscular body, situated within the cavity of the chest, and called the heart? Its figure is somewhat conical, and it is externally divided into two parts: the base, which is uppermost, and attached to vessels; and the apex, which is loose and pointing to the left side, against which it beats. Its substance is muscular, being composed of fleshy fibres, interwoven with each other. It is divided internally into cavities, called auricles and ventricles; from which vessels proceed to convey the blood to the different parts of the body. The ventricles are situated in the substance of the heart, and are separated from each other by a thick muscular substance; they are divided into right and left, and each communicates with its adjoining auricle, one of which is situated on each side the base of the heart. The right auricle receives the blood from the head and superior parts of the body, by means of a large vein; and in the same manner the blood is returned to it from the inferior parts, by all the veins emptying their stores into one, which terminates in this ca vity; which, having received a sufficient portion of blood, contracts, and by this motion empties itself into the right ventricle, which also contracting propels the blood into an artery, which immediately conveys it into the lungs, where it undergoes certain changes, and then passes through veins into the left auricle of the heart, thence into the left ventricle, by the contraction of which it is forced into an artery, through whose ramifications it is dispersed to all parts of the body, from which it is again returned to the right auricle; thus keeping up a perpetual circulation: for, whilst life remains, the action of the heart never ceases. In a state of health the heart contracts about seventy times in a minute, and is supposed at each contraction to propel about two ounces of blood; to do which, the force it exerts is very considerable, though neither the quantity of force exerted, nor of blood propelled, is accurately determined. The heart comprises within itself a world of wonders; and whilst we admire its admirable structure and properties, we are naturally led to consider the wisdom and power of Him who formed it, from whom first proceeded the circulation of the blood and the pulsations of the heart; who commands it to be still, and all the functions instantly cease to act: in God alone we live, move, and have our being; and may we never, whilst the vital stream flows through our veins, forget his goodness, or repay his love with ingratitude! MARCH XX. The Change of Seasons. THE coldest as well as the warmest climates have but two seasons in the year, which are essentially different. In the coldest countries the summer continues about four months, during which the heat is very powerful; the rest of their year may be considered as winter. Their spring and autumn are scarcely perceptible, because in the space of only a few |