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a work. When, however, the Sankey Canal had been made, the case was different. It was believed that Englishmen could make canals, and there was one Englishman who seemed to believe that he could make any canal in any place. This man came forward and told the duke that he would make the canal from the coal-mines at Worsley to Manchester; it was

true that there were immense difficulties, but they could be surmounted. "And he felt sure," he said, "that he would surmount them, if the duke would let him try.” And the duke did so.

The name of this man was JAMES BRINDLEY; but who he was, and what he did, I have not time to tell you now. You shall hear about him next week.

INDUSTRY.

PAUSE not to dream of the future before us,
Pause not to weep the wild cares that come o'er us;
Hark how Creation's deep musical chorus,

Unintermitting, goes up into Heaven!

Never the ocean wave falters in flowing;
Never the little seed stops in its growing;
More and more richly the rose-heart keeps glowing,
Till from its nourishing stem it is riven.

"Labour is worship!"-the robin is singing;
"Labour is worship!"-the wild bee is ringing;
Listen! that eloquent whisper, upspringing,
Speaks to thy soul from out nature's heart.
From the dark cloud flows the life-giving shower;
From the rough sod comes the soft-breathing flower;
From the small insect the rich coral bower;

Only man, in the plan, ever shrinks from his part.
Labour is life! 'Tis the still water faileth;
Idleness ever despaireth, bewaileth:

Keep the watch wound, for the dark rust assaileth;
Flowers droop and die in the stillness of noon.
Labour is glory!-the flying cloud lightens;
Only the waving wing changes and brightens;
Idle hearts only the dark future frightens :

Play the sweet keys, wouldst thou keep them in tune.
Labour is rest from the sorrows that greet us;
Rest from all petty vexations that meet us;
Rest from sin-promptings that ever entreat us;
Rest from world-syrens that lure us to ill.
Work!-and pure slumbers shall wait on thy pillow:
Work!-thou shalt ride over care's coming billow;
Lie not down wearied 'neath wo's weeping willow:
Work with a stout heart and resolute will!

MRS. FRANCES OSGOOD.

CHAPTER II.

THE PARTS OF A PLANT-THE STEM.

L. You have talked to us, papa, of the distinctions between a plant and an animal; and you began to describe the parts of a plant.

P. Yes; we noticed the root: to-day we will examine the stem. The root you described as the part which grows downwards-from the light-into the earth.

Ion. So the stem grows upwards-towards the light-in the air. We do not always call this part 66 stem"; sometimes we say stalk, and sometimes trunk.

P. True; now for the parts of this part-or its organs, we may say. Here is a piece of wood from a Beech-tree. I

have cut the branch across. Now examine it, and see how many parts you notice.

Ion. I observe the inside part, the pith.

W. Secondly, the outside part, the bark.

L. Thirdly, the wood between the bark and the pith. There are two kinds-the inside wood,

near the pith, is dark; and that nearer the bark is light.

P. The darker part is called the heart-wood, and the lighter part the sap-wood. What else do you see?

Ion. I see some lines drawn from the centre to the circumference of the circle; radii, I should call them.

P. Or, as you are not learning drawing, you may use a plain English word, rays. These rays begin from the pith; and as the Latin for pith is medulla, we call them the medullary rays. Are there any other parts?

W. Yes; please let me have a piece of the wood to bite. Look, papa, now I have bitten it! I can pull the wood and the bark into shreds-you call them fibres; they are "parts" of the

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stem.

P. Certainly; and as they do not fit closely together in the wood, but are interwoven, there are spaces between them which we call cells.

Ion. And what is all this wet which has come out from the stick since Willie has bitten it? Is it sap?

P. Yes; that was contained in the cells. There is another part which you cannot well observe; it is a thin membrane, which serves as a bark or sheath to the pith. It is called the medullary sheath.

L. Now I will count up the parts we have noticed:-The pith-bark-heart-wood-sap

wood-medullary sheath-me- bark of our apple tree is; but dullary rays-fibres — cells — of course the bark which coand sap. vered it when it was as thin as mamma's netting-needle, is not large enough now that its stem is so thick.

P. You have noticed the names of these parts; we will next talk of their growth, and their uses.

When the young plant has been growing one year, it merely consists of the pith, a thin circle of wood, and a thin circle of bark. By the end of the next year, however, there are two circles of wood, and two of bark. The second circle of wood is formed outside the previous one; and the second circle of bark is formed inside the old one-thus the two new circles touch each other. Can you understand that?

Ion. Yes; they must touch

each other.

P. The next year there will be three layers of wood and three of bark; a new layer of wood being added outside that of the last year, and a new layer of bark within that of the last year. The next year there are four layers of each substance; the next year five; and so on, new circular layers being formed every year.

L. So I suppose that by counting the circles we might tell how old a tree is?

P. Yes; by counting the circles of wood, but not those of the bark, for they are not all perfect. You know that the thin outside circle of the bark has to stretch every year as the tree grows; therefore it must at last crack. Thus it is that the stem has so rough an appearance outside.

W. Yes, how very rough the

P. This piece of stem from the Beech, because it grows in the manner I have described, is called an EXOGEN, which means growing outside. There are other kinds of stems, which we shall talk of soon; but they are not so common in temperate countries as the Exogens. All the trees and shrubs of this country, such as the Ash, Oak, Beech, Fir, Apple, Pear, &c., are exogens. You may know them by their numerous branches, which are not found in the other kind of stems.

Now that you have noticed the parts of the stem, let us speak of their functions (or uses).

What is the use of the pith? When the plant is very young, if you break its stalk you will hardly observe the pith. This is because it is filled with a greenish fluid, called sap. The sap is conveyed through the pith, up to the leaves and buds. But this is not always the case. When the plant is older, the sap ascends in another way. The pith, then, is not wanted; it becomes dry and dead; and it may be removed without destroying the plant.

Ion. Will you tell us the uses of the wood next, papa?

P. We shall see at once the functions of the woody fibre and cells, of the bark and of the medullary rays, if I give you the history of the sap and its

progress. What are the func- You were telling us about the tions of the sap?

You remember the thousands of little spongelets at the end of the rootlets. Imagine them working all day, very busy collecting the moisture to make sap. As they collect it, it ascends through the rootlets into the larger branches of the roots, and from them into the

stem.

L. But what makes it ascend; how can it rise upwards? I thought that water would never flow up?

P. How it is done I cannot tell; it is one of the "mysteries" of nature. But, oh! how wonderful it is! Think, next time you walk in the fields, of the sap rising in the dark earth underneath your feet! think of the millions of spongelets and rootlets there, all hard at work! they are working unseen, that the grass may grow, and beautify the earth. Yet how silently it is all done! there is no show, no fuss, no noise, no buzz. It is all done regularly, and it is done earnestly, for if there is but little moisture they extend further in the soil and deeper, until they find some. Talk about the bees! Bees are buzzing busybodies; but in all the earth there are no workers so silent, so humble, so out of sight, so unknown, unheard of, uncared for, as the dear little rootlets under the earth. What would the bees do, I wonder, if the rootlets did not work well?

W. Or, men either?

L. But, papa, how you are running on about the rootlets!

stem.

P. Or rather, I was speaking about the sap,-that it ascended the root into the stem. When the tree is a year or two old, the sap does not rise through the pith, but through the cells between the fibres of the wood. It ascends from the bottom of the trunk to the top, through the wood of the large branches, into the smaller ones, into the little twigs, the little leaf-stalks, and thence into the leaves.

W. And then it cannot go any further!

P. Yes, it can; then some of it ascends into the air. The watery part of the sap rises in the form of vapour, and the sap which remains is, of course, thicker than before; its nature is also altered, for it absorbs gases from the air, and becomes highly nutritious food for the plant. It then descends the tree; but it does not return the same way as it went. Instead of descending through the wood, it comes down through certain vessels in the bark.

You may easily prove that it descends through the bark by an experiment with any of the little trees in your garden. Tie a string tightly round the stem, so that the sap cannot pass; the bark will then swell very much, from the sap that accumulates.

.

L. And when the sap comes down the bark, where does it go to?

P. A portion of it passes from the bark into the medullary rays-and through them until it reaches the old circles of

wood which are nearest the pith. Here it remains, filling up all the pores, and becoming quite hard. The circles of wood thus filled up become quite solid and of a dark colour, and are called heart-wood, as I told you when it was pointed out to you in the drawing.

W. So you did, papa! Let us look at the drawing again (page 69). Now you see, Lucy, that the heart-wood is shaded, darker. But I should think such wood is a hindrance, because as the pores are filled up the sap cannot ascend through them. What is the function of the heart-wood, papa?

P. It is formed to give solidity and strength to the tree. If the stem were all sap-wood, it would bend about, and be blown down. Shall I give you an instance?

Ion. Yes, do, papa, please. P. I know a tree, at the bottom of our garden, which grows very fast. It makes broad green leaves, long green branches, and large bunches of green fruit every year; therefore it requires plenty of sap. Thus its stems are nearly all sapwood; so that if it had the presumption to try and stand upright, it would immediately be blown down. Moreover, the spaces between the woody fibres are very large, so that the sap may ascend rapidly: thus the stem is peculiarly weak.

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P. And we call it-? L. Our Vine. I think, papa, that we can now tell the functions of the stem's different parts.

(1.) The function of the PITH is to convey the sap upward when the plant is very youngafterwards it has no particular function.

P. True; and it is not therefore a vital part. There is an old hollow Oak-tree at your uncle's

the pith is completely cut away; yet the tree lives.

L. (2.) The SAP rises in the tree in a thin watery state, and descends in a thick glutinous state; its function is to form heart-wood.

P. It has many more than that; but I have only told you of the functions which relate to the history of the stem-it supplies nourishment for all parts, for the buds, leaves, flowers, and fruits.

L. (3.) The function of the SAP-WOOD is to convey the sap, through its pores or cells, up to the leaves.

(4.) The function of the bark is to convey down from the leaves; it is also useful as a covering to the tree.

P. Thus, both these are vital parts. If your uncle were to cut through the bark of his hollow oak, it could die, because the moisture would not descend; and if he cut through the sap-wood it must die, because the moisture could not ascend-there would be no communication between the root and the leaves.

L. (5.) The function of the MEDULLARY RAYS is to convey

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