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with honest, straightforward conduct in all parties — (for the other leads to a great deal of low cunning)—more consistent with the rights of industry—that the wages of labour should, in the case of the industrious man, be equal to all the decent wants of his class - house-rent, food, clothing, education; and in all cases of ordinary sickness, medical attendance—that the labourer should feel that it belongs to himself and to his own character, as an honest man, to provide all these things for himself and for his family-to feel happy in providing them every comfort within his reach ; but then it is equally necessary that the employer of labour should view the matter in the same light. And although it may be difficult to arrive at this. yet it is to be hoped the tendency of education will be to point in this direction, and to enlighten both as to their true interests — that the one will respect the rights of honest industry--that the other will no less duly estimate what is owing to the employer who acts on this straightforward, manly, and honest principle (and which ought to be the commercial principle) ; which, although making the labourer earn his living by the sweat of his brow, would place him in a situation of decent comfort – happy in him. self and in his family around him - happy in the blessings which this life affords him,* and equally happy in looking forward to leave it, when it shall please God to call him.

The arithmetical constants given below, with the tabular matter on the different subjects to which the tables relate. will, in the higher class of schools, be found of great

* “The common benefits of our nature entirely escape us; yet these are the great things. These constitute what most properly ought to be accounted blessings of Providence: what alonc, if we might so speak, are worthy of its care. Nightly rest and daily bread, the ordinary use of our limbs, and senses, and understandings, are gifts which admit of no comparison with any other. Yet because almost every man we meet with possesses these, we leave them out of our enumeration. They raise no sentiment: they move no gratitude.”—PALEY's Natural Theology.

service. Some of the walls of the class-room of the King's Somborne school are plastered, and the following matter, in a tabulated form, written upon them, in letters and figures of about an inch in size. They not only suggest observations during the progress of a lesson connected with the subject of them, but they accustom the teacher to something like arithmetical accuracy in making such observations, and enable the children to form ideas of a definite kind, and make the subjects perfectly intelligible; in fact, knowledge communicated in this way makes them close and accurate reasoners, and it is astonishing to see how much they get interested in it. These tables also suggest numberless questions in arithmetic which may be given by a teacher. In giving them here, it is merely to suggest the same things to others, and in schools, where such information is not a part of their teaching, tabular matter, connected with the ordinary weights and measures — the number of cubic inches in a solid yard, in a quart, and other measures, might supply its place on the walls of the school-room.

From Table I.-In comparing the rapidity of the motion of a cannon-ball with that, for instance, of the swallow, the teacher would point out the necessity of reducing them to spaces passed over in the same time, when it will be found that the cannon-ball moves at the rate of more than 1300 miles per hour, the swallow, 90; that one is a velocity so great that the eye cannot see the object moving ; that there is an intermediate velocity between the two, with which, if the ball moves, it ceases to be invisible, and that it will be gradually reduced to this before its motion ceases -after striking the ground — which is called a spent ball ; that the flight of the bird may be supposed to be so increased, as not to be seen in passing from one point of space to another, etc.

The outline of Table VIII, which is only partially filled up, would suggest many observations of a meteorological kind — why points of equal temperature on the surface of the earth do not follow the simple rule of distance from the equator; how affected by sea, land, mountains ; accounting for the zig-zag nature of isothermal lines, etc. It would

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also be found very useful to draw on the ceiling of the school or class-room lines running in the direction of the four cardinal points, with a line representing the magnetic meridian in degrees, and the magnitude of the angle of yariation written between them.

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Table 1.—Numerical Constants. ce of a circle, dia. 1 . .

3:14159 Area of do.

•7854 Oce of a circle, dia. D. .

(3:14159) D Area of do.

(7854) D? Length of Arc 1° dia. 1

•008726645
Sol. cylinder Ht D and dia. of Base D=(7854) D3

,, of sphere = į of cylinder =(•5236) D3
Surface of do. dia. D ..

. . (3:14159) D?
A body falls by gravity . . 16,'feet in 1" }

. (166) t in thi
Length of a pendulum vibrating ¿ .
seconds in lat. 51° 311

{ = 39.1386 inches.

-
Velocity of sound .

. . 1142 feet in 101
of a cannon-ball . . 2000 feet in 10
of light . . . . 200,000 miles in lov
of rotation of point at equator 1520 feet per second.
of a point in lat. 519 . 830
of a musket-ball.

1280
of a rifle . . . 1600
of a 24 lb. shot . • 2400
of quick train railroad . 88
(mean) of rivers .

3 or 4

13
of a brisk wind . . 10 miles per hour.
of a high wind, about. 40
of a hurricane .

80
Most rapid flight of a swallow, about 80 to 90 »

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Table II.---Time of Light travelling from the Sun to

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Mercury................................. 0
Venus..........
Earth.
Mars
Jupiter ........
Saturn.
Uranus

is .......................
Neptune.....................
Fixed stars ..................

13 20 29

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TABLE III.*-Specific Gravity, Distilled Water=1.000.

METALS.

LIQUIDS. And other Inorganic Bodies. . Sea Water ............... 1.026

Milk ..............

1.030 Platinum 22.069 Zinc .... 7.100

| Oil of Olives ...........

0.915 Gold .... 19.258 Sodium.. 0.973

Alcohol .............

0.792 Mercury. 13.586 Potassium 0856

Ether .................

0:715 Lead .... 11:352 Chalk.... 2:784

Nitric Acid ............ 1.503 Silver .. 10:474 Limestone 3.179 |

Sulphuric Acid.......... 1.845 Copper.. 8.788 Marble.. 2:742 |

Ammonia................

09.60 Steel .... 7.812 Flint and Iron (bar) 70788 Spar. 2.594

Weight, in ounces, of a)

cubic foot of water, { 997•136 Iron(cast) 7.207 Common

temp. 63o .......... Tin...... 7.2911 Glass.. 2.642

Ditto in lbs. ............ 62321 ORGANIC BODIES.

GASES. Dry Oak

.925 Beech ..............

•852 | Atmospheric Air ....... 1.000 » Ash ... .845 Oxygen ..........

1•111 , Elm ..........

-600 Nitrogen .............. 0.972 Cedar .............. •561 | Hydrogen...............

0:069 Larch ............., .498 Chlorine ................

2.500 Poplar .............. 383 Ammonia .............

0:590 Cork ..............

.240 Carbonic Acid .......... 1.527 » Ivory ............ 1.826 | Weight, in ounces, of a ?

1.24642 » Bones of Oxen .... 1.656 cubic foot of air ....S

| Ditto in lbs. ............

0779

* Tables of this kind in large print, and on pasteboard, would be very useful in schools ; such as those arranged by Mr. Tegetmeir, and published by Messrs. Groombridge.

26

28

Water ...............

2120

Lard .....

TABLE IV.*
Height of

Corresponding temperature
Barometer.

at which water boils.
Inches.

Fahrenheit.

204.91° 26.5

205.79 27

206.67 27.5

207.55

208:43 28.5

209.31 29

210.10 29.5

211.07 30

212.00 30-5

212.88 31•

213.76 These inches of mercury measure also the elastic force of the vapour of water at the same temperature. TABLE V.

TABLE VI.
Melting Points of different

Boiling Points of different
Substances.

Liquids.
Fah.

Fah.
Heat of Common Fire.. 790°
Iron red in the dark .... 750 Ether .................... 96
Beeswax ................ 136 Alcohol .. ..........

176 97 Most Essential oils ...... 212 Tallow .... 127 Water saturated with

225 Tin, 3. Lead, 2 ...... 334 common salt ........ S Tin, 1. Lead, 4 ...... 460 Oil of Turpentine ........ 316 Lead ....................

612 Sulphuric Acid ......... 590 Zinc ....................

680 Linseed Oil .............. Antimony ....... ......

809
Mercury ................

660 Brass ................... 3809 Nitric Acid ............

248 Copper ................. 4587 Phosphorus ........ .....

554 Silver .................. 3937 Sulphnr .................. 5

570 Gold ..........

5237 Soft Nails..............

21097 Iron...........

21637 Platinum

23177
TABLE VII.-Freezing Points of Liquids.

Fah.
Water freezes ............

32° Mercury ................ Milk. Olive Oil ......

Oil of Turpentine ...... Salt Water,

Sulphuric Acid ........ +46 1 part salt, 4 parts water .. 1 Human Blood

+ 25 Brine, 1 part salt, 3 water.. 4 | Brandy ................

+ 7 * Tables IV, V, VI, VII, from Lardner's Cyclopædia, volume on Heat.

600

30

Vinegar .......

36

I+++

Dol..........

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