"Those are where the annual layers of cells, or of what is called 'the cellular tissue,' are compressed as they run across the cells which make the lace-work of the cutting. All cone-bearing trees, as the pine, cedar, spruce, hemlock, and the like, have the same compact and beautiful structure, like the closest woven lace. A cutting along the lengthway of the stick will give you a new beauty and a new idea of the structure of the wood. What see you, Johnny?" "Oh, my! I see the shelves in the buttery, and the plates all set up in rows on them, and sometimes two rows on a shelf; of silver and glass the plates are, and the shelves are pearl, I guess; you see if they are not, sis!"

"Yes, they seem so, Johnny; but you know we are looking at a lengthwise cutting of pine wood. What is the meaning of this ap pearance, Uncle George?"

"The shelves or lines which run through the field are the sides of the sap-tubes, whose ends were seen in the other view. Between these, the glass plates which Johnny saw are called glands. These are never found with more than two rows between the tubes, and generally with but one. They are mostly circular, often oval, and sometimes crowded into angular shapes. They are very minute, not measuring more than the five hundreth part of an inch. Those who see the structure of wood only in pictures can have no adequate idea of its beauty.

"On the following page is an engraving giving a magnified representation of a section of white oak, which, though solid and heavy as compared with pine, yet shows a contrast as remarkable in the enormous pores or sap-tubes which it contains. You see in the field one of the more solid bands which radiate from the center, composed of cells so minute that our microscope can not detect them; a hundred of them would be less than the point of a needle in breadth, and ten thousand of them could be covered by the point of the microscope

O

CUTTINGS OF WOOD.

resting directly over them, while one of the large tubes is not less than the twentieth of an inch. Irregular wavy lines, like the broad band, run in the same direction between these tubes. Some of the tubes, you will see, are very small, the largest being the first growth of each year, of which two are indicated in view. These tubes, as those of many other woods, are found by careful examiners to be formed by bands of woody fibers wound spirally round and round, as if you should twist a tape or ribbon into a pipe by winding it with the edges just overlapping each other.

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us.

SCHOOL-ROOM SONG.

"I will now show in succession a variety of the specimens before The sumach, with its thorn-like down covering the bark, and its arched clusters of cells spanning a round bundle of tubes, and its beautiful center of pith in rich honeycomb. And here is the ash, with a double row of minute vessels in circular clusters, one on the outer and one on the inner margin of the bark, while the lines radiating from the center are very numerous and very regular. The wood is close except at the commencement of the year's growth, where the large tubes are arranged like a profile view of a pyramid of cannon-balls.

"There is no end to the variety, even in apparent sameness, no end to the beautiful figures which sections of wood and various herbs present, but no description and no picture can sufficiently illustrate the wonderful delicacy and order which they display."

The engravings which illustrate the preceding article are from " Views of the Microscopic World," by Brocklesby-published by Messrs. Pratt, Woodford & Co., New York. Those who wish to investigate this subject more fully than it is here treated, will find that work one of extraordinary interest. It is illustrated with about 250 engravings.

SCHOOL-ROOM SONG.

Busy fly the happy hours

In our school-room cheery,

While we ply our lessons well,
Write, recite, and read, and spell,
Gay as bees among the flowers,
Always glad,

Never sad or weary.

Learning's spoil we strive to win,
In our school-room cheery;
For to man's estate we'll grow,
And the good and great we know,
Draw from stores of thought within.
So we toil

For the spoil so cheerily.

And we aim for noblest things,
In our school-room cheery.
Rills of good are bubbling forth
To enrich the gray old earth-

I KNOW

you do not feel like listening to a lecture in such hot weather, and that you had much rather be out in the beautiful fields, or in some shady grove, than to sit down within doors and hear any body lecture. But this time I will be very brief, and select for my subject the Dew, which you know cools the air and refreshes the earth in warm weather, and the subject I trust will prove a cooling refreshment to your minds.

It is now early in the morning, and the ground is still wet with the last night's moisture. All along the spires of grass, and on the leaves of all your beautiful garden flowers, hang the crystal drops. Among the many questions which young people like you are so continuously asking, I presume you have inquired, "Where does the dew come from?" That question has been asked by older heads than yours, and by philosophers, too. I suppose somebody has told you in reply that dew falls at night in an extremely fine rain, something like the mist of a foggy day. Let me assure you in the outset that this answer is wrong-dew does not fall in fine drops from the sky or clouds. Now I suppose you are ready to exclaim, " Then how does the dew come on the grass, and leaves, and flowers ?"

Before answering this interrogation I will state a few facts in nature, which, I think, will enable you to comprehend the reply to what may now appear to be an objection to my assertion. In a warm summer's day, if you fill a glass or pitcher with cold water from the well, you will soon observe that the outside is covered with moisture. All of my young friends must have observed this many times. Besides,

you have doubtless observed that drops of water, like dew, collect in very warm weather on the walls and stones of a cool cellar. Now who can tell me where the moisture and drops of water come from in these instances?

Perhaps some one has told you that the tumbler and pitcher "sweats," that the glass or stone, whichever it may be, is full of minute pores like your own skin, and that the water oozes through and moistens the outside. I have heard such explanations given. If such were the cause, moisture would collect on the surface of these vessels, when filled with water, in cold as freely as in warm weather. But it does not, and thus you can easily understand that such an answer must be false.

The atmosphere always contains water in the form of invisible vapor, which the sun's heat causes to ascend from the surface of the earth, as well as from water. Heat renders this vapor so rarefied and light, that its existence in the atmosphere is imperceptible to our senses. Now, when this warm air comes in contact with some cold substance, it condenses the invisible vapor in the air and water is formed in drops, just as you find it on the outside of a pitcher of icewater in a warm summer's day, or on the leaves and flowers of plants in the morning, or on the flagstones and walls of a cool cellar. We know that dew does not fall like a fine rain, if it did it would be found only on the upper surface of the leaves and flowers, but dew is found on the under side of the leaves also. Dew does not come from the clouds, for it is never found unless the sky is clear.

We We may, then, make these distinctions between rain and dew: rain falls; dew collects. Rain falls on all objects alike; dew selects the objects on which it collects. Rain falls on the earth, as well as on leaves and blossoms; dew has a preference for leaves and flowers, and avoids the barren earth.

Dew will not collect on grass and leaves unless they become cooler than the surrounding atmosphere, any more than moisture will collect on a pitcher of hot water in a warm day. This fact was ascertained by placing one thermometer among the leaves of plants and suspending another some three or four feet above them. The result was, the thermometer among the leaves indicated a temperature twenty degrees cooler than the one in the air. Dew does not collect on a cloudy night; and it has been ascertained, by the same experiment with thermometers, that on such nights the leaves of plants become no cooler than the air surrounding them.

The whole theory of dew may be summed up in a few words.