ut a body will be supported or will stead as line of direction fills within

ided it keeps its balance, so we skad

speech; and when we give a

ple, we are at the same time converse, namely, that a body vection falls without its base th ce. Now the reason of thi it is remembered that the attracte tendency to fall towards the conte equally on all parts of the same body quently, there is a point in every od which in every direction it acts equally. Cfound by experiment, that mon Jefry b Ray antiquity, are slightly mold indicular; the Monument, mas

of many instances,and towers at Caerphilly, B in addition to those alas The celebrated Belley, Pisa, stands just behind als singular structure, e small pretensions gether upright; at pres wonderful. H

LEANING TOWERS.

say

THESE curious specimens of architecture afford perhaps the most striking and remarkable examples in existence of that important principle in the laws of gravitation, that a body will be supported or will stand, provided that its line of direction falls within its base, -that is, provided it keeps its balance, as we should in common speech; and when we give our assent to this principle, we are at the same time giving our assent to its converse, namely, that a body will fall if its line of direction falls without its base,—that is, if it lose its balance. Now the reason of this will be obvious, when it is remembered that the attraction of gravitation, or tendency to fall towards the centre of the earth, acts equally on all parts of the same body, and that, consequently, there is a point in every body around which in every direction it acts equally. It has been found by experiment, that most lofty buildings, of any antiquity, are slightly inclined from the perpendicular; the Monument, near London Bridge, is one of many instances, and we may likewise mention the towers at Caerphilly, Bridgenorth, and Corfe Castle, in addition to those already mentioned.

The celebrated Belfry, or Leaning Tower of Pisa, stands just behind the cathedral of that city. This singular structure, Mr. Wood tells us, would have small pretensions to architectural beauty were it altogether upright; at present it is quite as pleasing as it is wonderful. He describes it as a cylinder surrounded on the ground with a wall, adorned with halfcolumns and arches, and above this with six columns

of stories supporting arches, leaving an open gallery in each story between the columns and the wall. Three of these columns follow the same line of inclination as that on the ground; the fourth is very little rectified; the fifth and sixth are in one line, but form a very perceptible angle with the work below. A seventh story, of smaller extent, which crowns the whole, is very nearly erect. "As to the obliquity of the tower," says Mr. Forsyth, "I am astonished that two opinions should still exist as to its cause." The Observatory, in the next street, has so far declined from the plumb line as to affect the astronomical calculations of the place. A neighbouring belfry declines to the same side, and both these evidently from a lapse in the soft soil in which water springs everywhere at the depth of six feet. This great tower therefore leans only from the same cause, and because it wants the support of contiguous buildings.

READING.

THE following several directions will be of great service to our young friends in private reading, if they are faithfully followed.

I. Read systematically. I mean by this, do not take up and read any books because they merely chance to fall in your way. You see on a neighbour's table a book which looks as if it were interesting, as you say, and you think you should like to read it. You borrow it, carry it home, and at some convenient time you begin. You soon, however, either from taking it up at a time when you were interested in something else, or from being frequently interrupted, or perhaps from the character of the book, find it rather dull, and, after wasting a few hours upon the first fifty pages, you tumble over the remainder of the leaves, and then send the book home. After a few days more, you find some other book by a similar accident, and pursue the same course. Such a method of attempting to acquire knowledge from books will only dissipate the mind, destroy all habits of accurate thinking, and unfit you for any intellectual progress.

But you must not go into the opposite extreme of drawing up for yourself a set of rules, and a system of reading full enough to occupy you for years, and then begin upon that, with the determination of confining yourself, at all hazards, rigidly to it. What I mean by systematic reading is this:

Reflect upon your circumstances and condition in life, and consider what sort of knowledge will most increase your usefulness and happiness. Then inquire of some judicious friend for proper books. If accident