the Kangaroos themselves, to which animals, indeed, it is very closely related. In many particulars, however, it differs from the Macropina already described, the head being short and broad, and the tail endowed with considerable prehensile power. The colour of the fur is a pale brown, pencilled with white, the lower portions of the body being of a somewhat lighter hue. The extremity of the tail, which is decorated with a tuft of longer hairs, is black.

This pretty little animal does not reside in crevices of rocks, etc., after the manner of the rock kangaroo, but constructs for itself a dwelling in a somewhat singular manner. Taking advantage of some natural hollow in the ground, it scoops out the soil until a convenient depth is attained. The next step is to cover this hollow with a roofing of grasses, etc., so arranged that it exactly coincides in height with the tops of the surrounding vegetation. This is so ingeniously managed by the animal that, except to the practised eye of the native hunter, which immediately detects the slightest inequality among the herbage, it is almost invisible, the work being so neatly performed that scarcely a sign betrays the presence of the cleverly constructed domicile.

The animal conveys the materials selected for her nest to the site of the intended dwelling in a somewhat curious manner. First procuring a considerable quantity of leaves, grasses, etc., she forms them into a kind of sheaf, round which she twists her tail, hopping off, thus laden with her burden, to the nest. As soon as the material thus collected is used, she sets off in search of a second supply, and so on until the requisite quantity has been obtained.

This animal is extremely common in New South Wales, but, owing to its nocturnal habits, is comparatively seldom seen, except by those who go in search of it. In spite of its small size it is wonderfully active, and will travel over the ground at a really wonderful speed should it be pursued or otherwise alarmed. When hard pressed it has, like the kangaroo itself, a curious habit of leaping off suddenly at right angles to its course, and concealing itself in some crevice, in the hope of escaping the observation of its pursuer.

IN the Kangaroo Rat (Hypsiprymnus minor), or Potoroo, as it is termed by the natives, we have one of the transitional links between the Macropina and the animals composing the next group of the marsupials, the general kangaroo form and appearance being preserved, while the power of leaping, and also of manipulating food and other objects with the forepaws, is altogether wanting. It is true that the animal is able to sit upright, after the fashion of the kangaroos, supporting itself by a kind of tripod formed of the hinder limbs and the tail. Here, however, the resemblance ceases, the mode of progression employed by the potoroo consisting of a curious gallop, very different from the powerful bounds of the preceding

animals.

The title of Kangaroo Rat is due to the nature of the tail, which is covered with scales, between which proceed a number of scattered hairs. It is not a very large animal, the total length being only some twentyeight inches, of which rather more than one-third is occupied by the tail.

The Kangaroo Rat is tolerably plentiful throughout New South Wales, and, not being so exclusively noc

turnal in its habits as is the Brush-tailed Bettong, is far more often seen. It feeds chiefly upon roots, which it extracts from the ground by means of its powerful claws, which form very efficient weapons for tearing up the soil.

Owing to the nature of its food, the potoroo is a terrible nuisance upon cultivated land, often causing severe loss to the agriculturist by its ceaseless ravages. The potato seems to be a particular favourite article of diet with the animal, which continues its depredations day after day in spite of the attempts which are made to check its destructive proceedings.

THE Kangaroo Hare (Lagorchestes leporoides) is not at all unlike the animal from which it derives its popular title-colour, form, and habits being so remarkably hare-like that the name of kangaroo hare is singularly appropriate. The fur is close, hard, and slightly curled.

When alarmed, the kangaroo hare can run with the most marvellous celerity, often baffling even the best hounds by its wonderful speed, and also by the facility with which it doubles when closely pursued. Although usually progressing by means of a rapid gallop, it is by no means destitute of leaping abilities, and, should occasion require, will often execute the most wonderful bounds.

The kangaroo hare appears seldom or never to be found in the neighbourhood of the sea-coast, but seems to be confined to the interior of the country, where it is tolerably abundant.

With the kangaroo hare we must conclude our account of the members forming the group of the kangaroos, and shall in our next paper proceed to describe some further examples of this curious tribe of animals, which form one of the most interesting of all the great families into which the mammalia are divided.

BEFORE doing so, however, we will cast a glance at the marsupium,' or pouch, from which these animals derive their scientific name.

Many zoologists doubt whether the name is a satisfactory one, because the pouch is nothing more than a fold of skin, and there are many undoubted marsupials in which the pouch is practically non-existent, a mere wrinkle marking its position. The peculiarities of the marsupial structure are more internal than external, and, moreover, belong more to the young than to the adult animal.

It is impossible to describe the structure fully without the use of many and elaborate diagrams; but I will mention one or two of the most remarkable details.

No matter how large or how small the marsupium may be, the marsupial bones are always present. Even in the duck-bill, or platypus, and echidna, the marsupial bones are present, though the animals are not in any respect marsupials, but belong to a totally different order. Moreover, the marsupial bones are found in both sexes, though, of course, the male possesses no pouch.

Now we come to a very remarkable structure in the immature marsupial.

When introduced into the pouch it is affixed to one of its mother's teats in such a way that instead of receiving the teat into its mouth, its head seems to be drawn over the teat. At this period of life the young

one has not sufficient muscular power to enable it to suck, and the milk is continually forced down its throat by the compression of certain muscles peculiar to these creatures.

Now, if the structure of the young marsupial-say a kangaroo-were like that of other mammals, the little creature would be choked by the flow of milk; so the entrances to the respiratory and nutritive organs are separated by the modification of certain portions of the throat into a valve, which permits the milk to flow continuously down the throat while the channel of respiration is kept open.

The structure of this portion of the immature marsupial is almost identical with that of the whale tribe. (To be continued.)

How I Teach Elementary Science.'

BY RICHARD BALCHIN,

Head Master of the Gloucester Road Board School, London.

FOURTH-SCHEDULE

'PARA

MECHANICS.

SUBJECTS:

ARALLELOGRAMS of forces and of velocities.' This somewhat ambitious title would lead many to consider that the subject treated of was rather outside the limits of elementary instruction. Nothing, however, ought to be so considered which is fairly within the mental capacity of our scholars. And that this subject can be grasped by ordinary fifth and sixth standard boys, I have had abundant proof. I may mention, as a fact, that on the occasion of my giving the first lesson upon it, I asked a boy to come out and draw a line to show the direction of the resultant of two forces whose directions I had indicated on the blackboard; and the lad drew a line which I found, on completing the parallelogram, to be exactly coincident with the diagonal; so clearly did he perceive the nature of the subject. The truth is, the general principles or laws which are observed in the workings of nature around us, can be made clear to boys, just in proportion to the clearness with which the teacher himself perceives those laws. I am attending a course of lectures by Professor Seeley, and I cannot but note the enormous difference between his demonstration of a truth and that of our ordinary certificated science teachers. When listening to some of the latter, how soon it becomes manifest that their knowledge of the subject reaches just as far as the last page of the sixpenny text-book, and no farther.

Instead of reproducing a lesson, I will, in this article, endeavour to make clear what is meant by parallelogram of forces. Force is that which produces motion. It is measured by the amount of momentum it communicates. Momentum is compounded of mass and velocity. Weight is a measure of mass. Velocity is measured by the space passed over in a certain time. Now all those truths must be entirely understood before pupils are able to grasp anything concerning parallelogram of forces. It must here be understood that we speak of mechanical force only, not of heat force, or electric force, or chemical force. Let us take a mass of matter weighing 4 lbs. Let the number 4 represent such mass. It moves at a velocity, say, of 3 ft. per second. Good. Now we

will compound the mass and velocity. Multiply 3 by 4, answer 12. Then 12 is a number which represents the momentum of a certain moving body. But the momentum of a body is a measure of the force which has communicated that momentum. Therefore, the number 12 may stand to represent a force. Again, take another mass weighing 3 lbs. Let its velocity be 2 ft. per second. Then the number which will represent its momentum will be 6, which may represent the force that has communicated this momentum. Here, then, we have two momenta, represented relatively by the numbers 12 and 6; and we say the first momentum is double of the second. Also we have two forces represented relatively by the same numbers. I have entered into these preliminaries somewhat in detail, because I so frequently hear and read such phrases as the following:-let a force of 4 lbs. act;' 'let the line AB represent the direction of a force of 12 lbs.,' and so on. Now are not such statements misleading? What is a force of 4 lbs.? Can there be such a thing as 4 lbs. of force? I cannot conceive of such. Of course, when we wish to represent the relativity of different forces, we may let numbers or lines stand for their magnitudes or intensities.

If two forces of equal magnitude act simultaneously from exactly opposite directions upon a given point, they entirely neutralize each other; or in more correct language they are entirely converted into a resultant of heat force; with which at present we have nothing to do.

If two forces, from different but not exactly opposite directions, act simultaneously upon a certain point, the resultant, both as to direction and intensity, may be represented by the diagonal of a parallelogram whose sides represent respectively the two forces. This is a statement of the parallelogram of forces. I need not, however, proceed further with the subject, as all the ordinary text-books fully explain it.

This article concludes the series on the methods I have adopted for teaching the Fourth Schedule Subject, Mechanics.' I trust that those of my readers who have not yet taken up the subject as a 'special' will be induced to do so. Not that they will neces sarily follow the lines I have laid down, for it is a subject that admits of an endless variety of treatment. In those articles I have confined myself more to the principles involved and of the methods of demonstrating those principles, rather than to their application to any of the practical businesses of life. But if I taught in a manufacturing centre, I should certainly arrange a syllabus for mechanics that would bear intimately upon the special industry of the locality. Suppose, for instance, my school were in Bermondsey. The syllabus should be framed so as to include the structure of skin, the nature of the various skin-coats of the pachydermata; something respecting the natural history of those animals whose hides yield leather; the chemistry of tanning, including the nature of tannic acid, and its action upon the gelatino-fibrous substance of the true skin; the sources of 'tannin,' whether as barks and other raw parts of trees, or as extracts such as 'gambir,' 'japonica,' etc. All these subjects might be taken in addition to the elementary principles of natural philosophy given in the code. And I am quite convinced, no inspector would object to such a syllabus, although it would not be at all points strictly coincident with the official syllabus. If

my school were at Burton-on-Trent, then I would arrange the work to include the scientific principles involved in brewing; and not a boy should leave my sixth standard without having the fact demonstrated beyond all manner of question, that the main business of the brewer was to utterly spoil vast quantities of valuable barley. To such an extent may we impart what is generally understood as technical knowledge. Still, however, we must not lose sight of the fact that science-teaching in our schools should always be educative rather than technical. That our chief work is not so much to turn out good tanners and brewers as to develop that general intelligence which will surely prove to be the primary element of success in whatever position of life our scholars may hereafter find themselves.

(1) Find by practice the value of 9017 suits at £3 16s. 4d. each. Ans. £34,414 17s. 8d. (2) A grocer bought 5 cwt. 2 qrs. of tea for £71 17s. 4d., of which 7 lbs. were spoiled. What would he gain or lose by selling the rest at 2s. 7 d. a lb.? Ans. £8 1s. 3 d. gain.

(3) A bill:-13 lb. of cheese at 8d. a lb., 3 boxes of figs (2 lb. each) at 7d. a lb., 4 doz. oranges at 1d. each, 9 boxes of tapers at 2s. 3d. per dozen boxes, lb. of tea at 4s. 4d. a lb., and 17 lb. of bacon at Iold. a lb. Ans. 1 19s. 2 d. (4) A man who works 10 hours a day does a piece of work in 4 days; how many hours would he have worked each day if he had taken 8 days? Ans. 58.

STANDARD VI.

(1) Find the value of +2 +4 +13+ 4 of 31 of . Ans. 8

(2) After spending of my money, I have 7s. old. left. How much had I at first? Ans. 9s. 9d. (3) Add together 75 of 20s., 75 of a guinea, of a crown, and 125 of 245. Ans. 1 17s. 6d. (4) Find by practice the value of 36 cwt. 2 qr. 14 lb. of spice, at £7 11s. 6d. per cwt.

Ans. £277 8s. 84d. (5) If a man can walk a certain distance in 1 hr. 18 min. 45 sec. by taking 76 steps a minute, how many steps a minute must he take to walk the same distance in 1 hr. 3 min. ? Ans. 95.

(6) Find the value of 1, and of 1÷, and reduce each answer to a decimal.

Ans. 70129+; 222727.

Grammar.

STANDARD III.

9)16929

Ans. 1881

54,316 94

59,742

14,894

5,105,704 Ans.

44,848 Ans.

nouns, in the piece given for dictation.

Select nouns, verbs, adjectives, adverbs, and pro

(Analyse and parse the words in italics.)

(A) There in the shadow of old Time

The halls beneath thee lie,

Which poured forth to the fields of yore
Our England's chivalry.

(B) How bravely and how solemnly

They stand 'midst oak and yew, Whence Crecy's yeomen haply formed The bow in the battle true.

Composition.

STANDARD VI.

(A) What occupation would you choose to follow after leave school? Give reasons for your choice. you (B) Write an account of two ways in which you would spend a holiday.

ANSWERS TO

Pupil Teachers' Examination Papers.

Nov. 25TH, 1882.

CANDIDATES.

Three hours and a half allowed for this paper.

Arithmetic,

44 × 9

FEMALES.

1. Make out the following bill :-81 lbs. tea, at 2s. 11d. per lb.; 99 lbs. coffee, at 1s. 74d. per lb. ; 54 lbs. cocoa, at Is. 5d. per lb.; 243 lbs. rice, at 2 d. per lb. ; 31 lbs. 8 oz. butter, at Is. 1od. per lb. ; 63 lbs. loaf sugar, at 74d. per lb. ; 108 lbs. moist sugar, at 34d. per lb. ; 38 lbs. 4 oz. bacon, at 10d. per lb.; 55 lbs. 2 oz. cheese, at 8d per lb.

= 14,773 10 O

=

at I at 10S, =

930,730 10 O 7,386 15 0

369 6 9

€938,486 11 9 Ans.

2. If the rates on a house, of which the rent is £63, be £9 16s. 3d., what is the rent of a house on which the rates amount to 11 8s. 11d.?

£9 16s. 3d. £11 8s. 114d. :: £63 : ?

4. Find the cost of 30 cwt. 3 qrs. 9 lbs. 12 oz. at £16 6s. 8d. per cwt.

I.

Grammar.

'Two brothers once did weeping part
On the edge of the sea so blue;
The one was fair and false at heart,
The other was gallant and true.'

(a) Point out and parse all the verbs and adjectives in the above.

(b) How do you know that the words 'the one' and 'the other' in the above are not adjectives?

(a) Two-numeral adj. numbering 'brothers.'

did part-intrans. reg. verb, indic. past indef. (=parted)
3rd pers. plur. agr. with subj. 'brothers.'
weeping irreg. trans. verb weep, wept, wept, incomplete
part. having an adverbial force, and at the same
time attributive to 'brothers.'

blue-adj. qual. 'sea.'

and Tantallon Castle, Dunbar, and round into the Firth of Forth, passing the Bass Rock, North Berwick, Prestonpans, with its salt manufacture, Musselburgh, Portobello, Leith (the Port of Edinburgh), Granton, a rival to Leith, Queensferry, Bo'ness, Grangemouth, Alloa, noted for its ales, and reach our destination, Stirling.

3. Where are the following articles made:-Silk goods, stockings, lace, gloves, needles, porcelain? Name towns as well as counties, and describe the situation of each.

Silk goods-Spitalfields (London); Manchester, on the Irwell in Lancashire; Macclesfield, in Cheshire; Coventry, in Warwick; Derby, on the Derwent. Stockings-Leicester on the Soar; Derby; Nottingham, near the Trent.

Lace-Nottingham; Derby; Tiverton and Honiton, in Devonshire; Buckinghamshire.

Gloves-Worcester; Yeovil, in Somerset ; Woodstock, in Oxford.

Needles-Chiefly at Redditch, in Worcestershire.

Porcelain-North of Staffordshire; Derbyshire; Leeds, on the Aire, in Yorkshire; Worcester.

Composition.

Write from dictation the passage given out by the Inspector.

Penmanship.

Poss. Obj.

one's

one

We can say, 'The one's heart was false, and the other's true.' Adjectives are not declinable words.

2. What kinds of adjectives admit of comparison? What do not?

Adjectives of quality and quantity, whose signification can be increased or diminished, admit of comparison.

Adjectives of distinction, and those whose signification cannot be increased or diminished, do not admit of comparison. As: right, left, wrong, square, two, three, this.

Geography.

Answer either Q. 2 or Q. 3, not both.

1. What is meant by the basin of a river? Illustrate your answer by referring to the basin of the Severn, describing the counties drained by it, and naming in order its principal tributaries.

The basin is the whole area or space of ground which supplies the water to a river. It comprises not only the valley of the main river itself, but those of all the rivers and streams which run into it with all the tributaries up to the water-parting of each.

The basin of the Severn commences at Plynlimmon, and is separated from that of the Thames by the Cotswold Hills; the Edge Hills separate it from that of the Great Ouse; and the Clent Hills divide it from the basin of the Trent. On the west the basin of the Severn is bounded by the Clee Hills, the Malvern Hills, and the hilly district of the Dean Forest.

The Severn flows through Montgomery, the best wooded country in Wales, very mountainous except along the valley of the Severn; through Shropshire, a rich agricultural county abounding in coal and iron; through Worcester, a county rich in grain, salt springs, and manufactures of porcelain, carpets, etc.; and through Gloucester, a fine county, rich in grain, fruit, and pasturage, with the remains of the ancient Forest of Dean in the west, rich in coal and iron mines.

The tributaries of the Severn are the Vyrnwy, the Teme, the Avon, the Wye, the Usk, and the Lower Avon.

3. Give a rule for finding the decimal point in dividing one decimal by another.

Divide 29 5625 by 6'25; 295625 by 625; and 295625 by 625. Rule.-Divide as if the divisor and dividend were whole numbers. If the number of places in the dividend exceed the number in the divisor, cut off from the quotient as many decimal places as are equal in number to this excess, prefixing ciphers if necessary.

If the number of places in the dividend is less than the number of places in the divisor, affix ciphers to the dividend until the number of places in the dividend equals the number of places in the divisor; the quotient up to this point of the division will be a whole number; if there be a remainder, and the division be carried on further, the figures in the quotient after this point will be decimals.