A JOURNAL OF INSTRUCTION FOR THE FAMILY AND THE SCHOOL 3rd Week. MONDAY. Moral Biography. INDUSTRY. THE MAN WHO MADE A STEAM-ENGINE. P. LET us think of James | the trouble to learn German, if Watt, the MATHEMATICAL IN- he had not seen Mr. Watt doing STRUMENT MAKER TO THE COL- SO. LEGE OF GLASGOW. His friends in Glasgow soon increased. Very learned men and great men of the college became his friends. One cele brated professor was delighted with him. He says, "When I was introduced to Mr. Watt, I only expected to find a workman, but was surprised to find a philosopher, as young as myself, and always ready to instruct me. I had the vanity to think myself very proficient in my studies, but I was rather mortified to find Watt so much my superior. Whenever any puzzle came in the way of us students, we went to Mr. Watt. Everything became to him the beginning of a new and serious study; we knew that he would not quit it until he had discovered its insignificancy, or made something of it. In order to read a certain work, he learned the German language; and so did I, to know what he was about." Thus you see how useful a good man may be by his example. W. Yes, I dare say that the professor would not have taken P. In another part of this gentleman's letter, you may read of a quality in Mr. Watt which I am sure you will also admire. It is said "Watt's superiority to us all was hidden under the most amiable candour, in allowing merit to every man." Do you understand that, Willie? W. Yes; that means that he thought other people to be as good as himself. P. True; and here is something better. I will read it:"He would often surmise things which others would only carry out, yet he would ascribe the whole merit to their ingenuity." How different was Watt from many other men! Have you not sometimes noticed how anxious men are for the world to know of all they have done! They wish to get very great praise for themselves, and "to make a noise in the world." L. Yes. You once told us, papa, that "empty vessels make the most sound." P. But Watt, you see, was anxious only to do good, and he willingly gave to others the praise. How much better that is! After he had been in Glasgow six years, he married his cousin, and was allowed to set up in business in the city, as an instrument-maker: his importance was thus increased. He became an engineer as well as an instrument-maker-and it is said that "he was consulted in the construction of canals, bridges, and other large works requiring skill." You can understand how delightful such pursuits were to Mr. Watt. In everything he did, he worked at it with all his heart, for every new engagement was, as you heard, the beginning of a new and serious study. With this habit of mind, nothing came amiss to him. For instance: he was quite unacquainted with music; he had never been able in his life to sing, or play on any instrument, yet he one day astonished all his friends, by producing a fine organ, which he had built, and which contained many improvements. When some musicians played upon it, they found that it had a wonderful power of producing sound. What a thoughtful man he must have been to make this! You may now understand how pleased Mr. Watt would be, when, in the midst of his engagements, his attention was drawn to a model of a steam-engine. He had heard of steam-engines before, and Ion. But, papa, did not Mr. Watt invent the steam-engine? P. By no means. There had been many steam-engines before his time. I think you would like to hear their history. Nearly two thousand years ago, a Greek writer named HERO, who lived in Alexandria, in Egypt, described a toy which he had invented, and which had been moved by steam. In A.D. 540, an architect named ANTHEMIUS shook a house by the power of the steam from several cauldrons of water. On the 17th June, 1543, a man named BLASCO DE CAROY made a fine experiment in Spain; he procured a ship of 209 tons, and put it in a great cauldron of boiling water, with a moveable wheel on each side of the ship, by which he moved it; the experiment succeeded, but no one saw its value, and it was forgotten. In the year 1663, the first idea of a steam-engine came out in England. The MARQUIS OF WORCESTER published an account of one in a book. After describing it, he says "I call this a semi-omnipotent engine, and do intend that a model of it be buried with me." L. That seems very selfish! I wonder what that was for. P. I cannot say. He afterwards invented another engine, for draining all sorts of mines, which he declared to be "the most stupendous work in the whole world." This engine of the Marquis did not come into use until about thirty years after his death, when CAPTAIN THOMAS | SAVARY brought into use an engine for draining mineswhich he styled "The Miner's Friend." The engines of Savary, how ! ever, were not perfect; but in the year 1705 they were greatly improved by two Englishmen THOMAS NEWCOMEN, an ironmonger, and JOHN COWLEY, a glazier. They constructed a machine in imitation of one by a Frenchman named PAPIN. This was altogether superior to | any that had yet been made; it soon became very popular, and all over the country it was used for draining mines, for driving mills, and many other purposes. It was a model of Newcomen's engine which Mr. Watt met with when he was in business in Glasgow. Can you not imagine the man as he first sat down to examine it? "Ah!" he would cry aloud, "I have something here to look at!" and he would at once "make it a new and serious study." How carefully he would move all the parts to see how they acted! Then how slowly would he take it all to pieces, that he might repair the broken part-for it had been sent to him to be mended. Soon every part was thoroughly investigated; it was repaired, put together again, and made to work. When he was a boy and counted the drops from the steam of his aunt's kettle, he had learned to think; and from the habits he *had then formed, it was easy to understand the machine before him. He seemed to feel a relationship for the whole thing he took to it naturally, as a duck does to the water. It is likely that he had much greater knowledge than that of Newcomen. He had, of course, profound mathematical know ledge, and he brought that to bear on the engine; he had a knowledge of mechanics, of chemistry, and of nature's secret laws; and all this was useful to him. He "rummaged" the vast stores which he had been laying up since he was a boy, and brought out old thoughts to improve his new friend. Soon an improvement in one part was made; the defects of another part were seen, and they were remedied. A third part was altered, and before long he made a fresh model, which was in many points more perfect than that which he had repaired. He set to work to think more yet; he calculated "how much the water dilated in passing from its liquid state into steam; he discovered how much water a certain weight of coal would vaporize; how much vapour was expended for each stroke of the engine; and, lastly, the difference in the elasticity of steam at different temperatures. It is said that these difficult questions would have occupied the lifetime of many a laborious philosopher. But they did not cost so much to Watt. When do you suppose he performed all this work? It was principally done after his hours of business, without interfering with the labours of his workshop. Perhaps you can tell me when he formed such habits. W. Yes; when he was a boy they grew up with him. P. And that is the reason they were so strong; they were begun in his boyhood. You shall hear more of his model next week. (Continued on page 49.) CHAPTER I. THE DISTINCTIONS OF PLANTS. P. LAST week I finished our lesson with some remarks on the life of a plant. Ion. You were speaking again of the conditions of its life. You said that it must have organs, and that the organs must perform certain functions. P. True. We said how remarkable is the function of these organs to convert water and air into a beautiful treethe "function of nutrition," as it is called. They have another important function. By means of these organs the plant can resist the action of the elements around it. W. What would "the elements" do if the organs did not resist? P. They would cause it to decay-but as long as the organs perform their functions of growth, they can resist such action. Suppose, however, that you break off a twig from a tree -the organs in its leaves, and stem, lose their connection with the root. W. Yes, that is certain. P. Then they cease to perform their functions; the leaves fade and wither, and the stem becomes shrivelled. The twig can no longer resist the action of the air, which, in the course of a few years, reduces it to dust again. W. While perhaps the fellow twig-the one which grew beside it-has by that time become a great sturdy branch, caring nothing for wind or weather; but that branch cannot always grow. P. No; as I said, everything that lives must die. It cannot perform its functions for ever; and directly the sturdy branch ceases to grow it begins to die. L. I understand that. Just like the twig which was broken off; its organs cease to perform their functions; they cannot feed on the gases of the air to support life, so other gases feed on them and cause their death. P. That is pretty near the truth. And this leads us to a third condition of life; it is limited. Some plants grow up and die within a year; they are called annual plants. Others grow and die within two years; they are called biennials. Others do not live more than three or four years; while the giant, slow-growing trees live hundreds, and even thousands of years. But it has been supposed that the Creator has fixed a limit even to the number of years of their long lifetime. Now repeat the distinctions of a plant. W. I think I can say them. A PLANT has (1.) life, therefore it has (2.) organs which have the function of nutrition, and the function of resisting the rounding elements. sur But the organs cannot do this for ever; therefore it has (3.) a limit to its life, or, as we say, death. Ion. Then in the winter the trees are like th torpid ani In this way all plants might die; P. True. There is another There are other interesting instance in the vegetable kingpoints in plants. (5.) Their parts depend upon one another; (6.) they dom, where there seems to be consist of fluid and solid substance; life, yet the organs do not (7.) their substance is always surrounded by a covering, or skin; (8.) they are limited in size; (9.) they are fixed and decided in shape. You cannot say any of these things of a mineral, which never has life. Ion. Before you begin to describe the parts of a plant, papa, I want to ask something. You said when plants cease to grow they begin to decay. Do the trees grow in winter? P. No; but here you may see a curious law, like that you see in the animals: the trees may be almost said to be asleep. The functions of the organs are stopped, or suspended, as we say, until the sun warms them, and sets them to work again. perform their functions. You may keep a seed for many years; during all this time the little organs within it are quiet, and remain in the same condition. Yet it cannot be said to be dead, for you know that if you put it in the ground it will form a new plant. Its organs of nutrition will perform their functions as soon as sufficient heat and moisture have acted upon it, and have awakened it. W. We may say, then, I suppose, that it has life, but it is not in circumstances to act; it is sleepy P. Dormant we say; the live seed lies in a dormant state, just as a live animal lies in a torpid state. TO MY BROTHER. We are but two-the others sleep We in one mother's arms were locked Long be her love repaid! We are but one-be that the bond CHARLES SPRAGUE. |