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animalcules as they are called, have been found alive in the cells of certain water plants.
5. Starch also is abundantly met with in the cells of plants. It is found in their roots, stems, seeds, and
fruits, where nature has caused it to be stored for the nourishment of the plant in the following year. In the Potato and common Pea the starch is present in the form of small white grains, lying separate the one from the other within the cells, whereas in the Arrow-root and Sago plants the grains are clustered together.
6. Arrow-root indeed, is nothing but the starch obtained from the roots of certain tropical plants, whereas sago is extracted from the pith of a species of palm found in the East India Islands. “The tree is split so as to expose the pith, which is mixed with water, and the starch having been separated from the woody fibre, is pressed through a perforated metallic plate which moulds it into small cylinders. These are placed in a revolving vessel and broken into rough spherical grains which are steamed upon a sieve and dried.”
7. Sailors tell us that the inhabitants of Otaheite actually prepare bread, by simply placing upon a gridiron slices of a large fruit which grows in their island, and that these, when they are taken from the gridiron, have precisely the taste of the bread made by our bakers. This is easily explained. The fruit of the Bread-fruit tree, for so it is called, generally weighing more than two pounds and sometimes four or five, is filled with those nutritious grains, and only requires to be sliced down and exposed to heat in order to be transformed into genuine warm bread.—Compiled.
Questions on the lesson :-The instrument referred to? What service it renders to us? The great fact it has taught about the vegetable world? How small are the cells sometimes? Their shape? What force have they? When combined what do they form? What illustration is given of the rapidity of their growth? What are found in these cells? In the cells of what plants is starch found? What is said of Arrow-root? Sago? Where and how is bread obtained from a tree?
Otaheite, or Tahiti, the largest of the Society Islands. It is 120 miles in circumference, and is celebrated for the beauty of its scenery, and especially its cascades.
Fungus, plural fungi, plants entirely composed of cells, having
neither leaves, nor stems, nor roots. Fungi are attached to the substances on which they grow by whitish filaments called spawn. The filaments spread out like a net-work and nourish the plant.
beautiful green colour: the matter which gives the green colour to plants is called chlorophyll. It is said to be a coloured fatty or wax-like substance. It is not produced when light is absent. The varied tints which leaves assume in autumn are due to changes which have passed over this substance.
THE BENEFITS OF PAIN.
1. Sir Humphry Davy, when a boy, with the defiant constancy of youth which had as yet suffered nothing, held the opinion that pain was no evil. He was refuted by a crab which bit his toe when he was bathing, and made him roar loud enough to be heard half a mile off. If he had maintained instead that pain was a good, his doctrine would have been unimpeachable.
2. Unless the whole constitution of the world were altered, our very existence depends upon our sensibility to suffering. An anecdote which is quoted by Dr. Carpenter shows the fatal effects of a temporary suspension of this law of our nature. A drover went to sleep on a winter's evening upon the platform of a lime-kiln, with one leg resting upon the stones which had been piled up to burn through the night. That which was gentle warmth when he lay down became a consuming fire before he rose up.
His foot was burned off above the ankle, and when, roused in the morning by the man who superintended the lime-kiln, he put his stump unconscious of his misfortune to the ground, the extremity crumbled to atoms. Whether he had been lulled into torpor by the carbonic acid, or whatever else may have been the cause of his insensibility he felt no pain, and
through this very exemption from the lot of humanity expired a fortnight afterwards.
3. Without the warning voice of pain, life would be a series of similar disasters. Without physical pain, infancy would be maimed or perish before experience could inform it of its dangers. Without pain we could not proportion our actions to the strength of our frame or our exertions to its powers of endurance. In the impetuosity of youth we should strike blows that would crush our hands and break our arms, we should take leaps that would dislocate our limbs, and no longer taught by fatigue that the muscles needed repose, we should continue our sports and our walking tours till we had worn out the living tissue with the same unconsciousness with which we now wear out our coats and shoes.
4. Sir Charles Bell mentions the case of a patient who had lost the sense of heat in his right hand, and who, unconscious that the cover of a pan which had fallen into the fire was burning hot, took it out and deliberately returned it to its proper place, to the destruction of the skin of the palm and fingers. This itself would be an accident of incessant occurrence if the monitor were wanting which makes us drop such materials more hastily than we pick them up. Pain is the grand preserver of existence, the sleepless sentinel that watches over our safety, and makes us both start away from the injury that is present, and guard against it carefully for the time to come.
5. The same infinite wisdom which has contrived pain for our protection has also distributed it in the manner which causes it to fulfil its defensive purposes with the least suffering to its subjects. The skin is the most advanced guard through which every injury to the other parts must make its way. The skin, therefore, required
to be the seat of a peculiar sensibility both for its own security and to impel us to flinch from the violence which would hurt the flesh beneath. Forming our ideas of pain from what we feel at the surface, we imbibe the idea that the deeper the wound the more severe would be the suffering, but this is delusion and contrary to the fact. 6. The
surgeon who makes use of the knife informs the patient that the worst is over when the skin is passed, and if in the progress of the operation it is found necessary to extend the outer incision, the return to the skin proves far more trying than the original cut, from the contrast which it presents to the comparative insensibility of the interior. The muscle is protected not by its own tenderness, which is by no means acute, but by the tenderness of its superficial covering, which affords a more effectual defence than if our bodies were clothed with the hide of a rhinoceros.
7. To have endowed the delicate internal textures with an exquisite susceptibility to the gash from a knife or a blow from a stick would have been superfluous torture ! The end is effectually attained by spreading over them a thin layer of highly sensitive skin, which is too intolerant of cuts or bruises to allow any harm to approach it, which it is in our power to avert. In addition to the protection which is thus provided against occasional dangers, the skin by its sensibility is essential to our existence under the hourly conditions of life.
8. It is the skin which acts as a thermometer to tell us whether the temperature is suited to our organisation, and warns us alike to shun pernicious extremes of heat and cold. It is the skin again which prompts the instinctive restlessness that preserves the entire frame from decay. in the unconsciousness of slumb trivance continues to act, and, were it otherwise, sleep,