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intervals from autumn to spring. They are always coverings, and the seed being hard is undigested. protected by tough coverings, hairy coats, or var- Examples: yew and spindle, wood berries. nished with resin (examples, elm, willow, chestnut). The other ways in which flowering plants multi
Flowers.—The parts of the flower should be ply are chiefly by off-shoots from the stem. Examples studied at first without dissection; later, the flowers are found in house-leeks, strawberries, couch may be taken to pieces carefully and the parts grass. Artificial propagation by cutting shows pinned out. The following will serve as useful also the reproductive power of the stem; begonias types : buttercup, sweet pea, primrose, tulip, can be “struck” from a single leaf. hyacinth, jonquil, crocus. Many bulbs planted The above is a brief and general sketch of a plan in autumn can be easily grown in a schoolroom, of work which has been tried with success in a under the care of the class : snowdrop, hyacinth, class of young children. Observations of what daffodil, narcissus, tulip. If a garden bed is avail. actually takes place in field and garden cannot fail able it will be found a never-failing source of to be a satisfactory foundation for future experiinterest and pleasure; window boxes are a good mental work in laboratory botany. Young children substitute if the garden is not attainable.
have not the sufficiently mature minds to realise In studying flowers and the uses of their parts the significance of any but very simple experiments much may be done by observation out of school. (such as have been described in this article), but The bright colour and strong scent attract insects they are keen and truthful students of outdoor to visit flowers; the solid advantages they take sights and sounds, and faithful reproducers of what away in the honey and pollen for food. The service they see, especially if encouraged to illustrate rendered in return is the conveyance of pollen from their impressions by drawing and painting. one plant to another of the same kind. Noting The children should keep a “Nature Calendar," these things leads to the understanding of polli. , in which they can enter each day any new obser. nation and the simpler methods by which it is vation they make about the seeds and plants which effected. Some plants are pollinated by creeping they are growing or watching elsewhere. The and short-tongued insects (buttercup, arum, hem- children should also be encouraged to collect fruits, lock); some flowers (pea, vetch, clover) are seeds, flowers, leaves, &c., and to arrange their specially adapted for bees, as the honey is concealed finds in an orderly manner. As much work as and bees have long tongues; the monkshood and possible should be done out of doors. The main foxglove are visited by humble-bees; pinks and object of such a course in Practical Botany is to honeysuckles by butterflies and moths. Trees, as train the power of accurate observation and prehazels and poplars, have inconspicuously coloured cision of expression, but perhaps the greatest good Aowers, but the flowers come before the leaves and is in awaking and stimulating an enduring love of in breezy spring so that the pollen is distributed by Nature. the wind. Grasses are another common instance of wind pollination.
Fruits.--A collection of dry fruits should be made throughout the year. Many edible fruits can
ACETYLENE AS A LABORATORY be bought at any time. In spring the fruits of the
HEATING AGENT. primrose and marsh marigold are to be found; in summer those of the buttercup, violet, poppy, and
By A. E. MUNBY, M.A. dandelion; and in autumn a countless number
Felsted School. of specimens are available, such as nuts of all kinds; clematis, rose-hips, haws, peas, beans, wall. HE use of acetylene gas for lighting has exflowers, &c.
tended so much during the last few years, The chief points to be noted by young children
and has proved such a boon to many who are the division into classes of superior and inferior have no gas or electric light at disposal, that it is fruits-shown by reference to the orange and remarkable that more has not been done to produce apple; the other great division into fruits which suitable apparatus for using the gas for heating. open, and fruits whose outer covering rots away or In these days, when laboratories are springing up is broken artificially before the seed can come out. in so many small places where coal gas is either A large number of different fruits should be com- not obtainable or prohibitive in price, the possipared and the identity of parts noted under bilities in connection with this use of the gas are diversity of appearance.
very great, and have only quite recently been The ways in which fruits open and seeds are utilised. The gas, containing as it does 92 per dispersed give scope for careful observation. Good cent. of carbon, requires, of course, special arexamples are seen in the poppy, iris, violet, honesty, rangements for its successful combustion. Calcium pea, and many others.
carbide, which produces the gas on contact with The dispersal of fruits and seeds by the wind is water, is now so well known that it is perhaps well shown in elm, maple, thistle, dandelion, and unnecessary to say anything about its production. clematis; other fruits and seeds have rough, The sole makers in this country, the Acetylene clinging surfaces, so that they are carried by Illuminating Company, share with the British animals. Examples: goose-grass cleavers ; Aluminium Company the energy derived from “burrs” or burdock. Seeds carried by birds or the Falls of Foyers for producing their carbide, other animals have generally attractive outside
and the office of the former Company is at 3,
Victoria Street, S.W. A good deal of carbide is desirable from a laboratory point of view, because made on the continent and varies considerably in they cause very rapid injury to platinum apparatus quality, the make of some firms being undoubtedly exposed to a Bunsen flame, and from an interesting good. A good carbide should yield on an average paper in the Chemical Society's Journal for Nofour and a half to five cubic feet of gas per pound, vember, it would seem that the ammonia is and can be obtained delivered in most places at probably not the lesser of the two offenders. The the present time for about £21 per ton, and as it last-mentioned impurity, benzene, may be produced is now usually packed in free non-returnable owing to over-heating in the generator by the drums, this represents the total cost.
polymerisation of the acetylene; the objection to The choice of a generator for acetylene is rather it from the heating point of view is that it tends beyond the scope of this article, but the report of to produce a zone of luminosity in the Bunsen the Committee on the Exhibition of Acetylene Aame. Generators held at the Imperial Institute in 1898, Various purifiers have been proposed having for and printed by Mr. Trounce, 10, Gough Square, their general object the oxidation of the phosphoFleet Street, or the elaborate work of Professor retted hygrogen, the neutralisation of the ammonia Lewes entitled "Acetylene," contains many draw- and the absorption of the benzene. Among others, ins and valuable details of a score or more of bleaching powder and an
aqueous acetic-acid generators now on the market.
solution mixed with chromic acid may be menmoney and a good water-supply are all available, tioned. The gas should pass through, not merely we think that a non-automatic generator, in which over, the purifier employed, which may be effected the whole of the gas to be used for a given period by making a solution, or milk, of the purifier with is generated at once, is to be recommended, espe- water, and exposing a large surface to the action cially as the pressure required for heating work, of the gas by impregnating some indifferent subwhich, it must be noted, is equal to six inches of stance such as coke or pumice with the liquid. water as against about three inches generally We have made one or two experiments with the arranged for a generator for lighting only, is object of finding the value of these two purifiers readily obtained. If an automatic generator be in removing the luminous zone from a "Bunsen employed, it is advisable to ascertain beforehand flame and decreasing the deteriorating effect of that this pressure can be obtained, and it should the gas on platinum. So far as such experiments be borne in mind, and if necessary impressed upon have gone, they seem to show that both considerthe makers, that this additional pressure tends to
ably decrease the action of the gas on platinum, the formation of more “after gas," so that the but that the acetic-acid mixture is the more efficastorage capacity of the gas holders should be in- cious. On the other hand, the bleaching powder creased. As regards the estimation of the size of has a marked effect in reducing the tendency to generator required, it will be found that some luminosity in the flame, though this effect does makers have a tendency to over-estimate the out- not seem to be very lasting; the acetic-acid mixput of their apparatus, and it will sometimes be ture, however, appears to have no effect in this found desirable, therefore, to install a machine a direction. size larger than appears to be actually necessary The construction of the Bunsen burner for on paper. Among automatic generators we may acetylene involves a consideration of the diameter recommend that of Messrs. Thorn and Hoddle, of the tube, which must be very small, to prevent 135, Victoria Street, S.W., as being compact and "striking back"; the aperture of the jet, which moderate in price, and we believe with their latest has only to deliver about a quarter as much gas improvements quite satisfactory. We believe this per time as in an ordinary Bunsen burner; and the firm to have been the first to modify a generator gas pressure, which must be high, in order that for heating purposes, and that they are alive to the injecting power may be sufficient to cause the the requirements of the additional pressure. We complete combustion of the gas. These factors, have not found, however, that their generators run of course, are intimately connected one with the very well coupled together when the installation other, and admit of very little latitude. In the requires more than one of the largest size, one Munby burner, as produced by Messrs. Gallenhaving a tendency to pump into the other. How- kamp and Co., of 19, Sun Street, Finsbury Square, ever, the firm claim to have improved the method E.C., the diameter of the tube used is five milliof balancing, and where a second machine is kept metres, and the jet is capable of delivering about merely in reserve, this of course does not form any one cubic foot of acetylene per hour under the objection.
pressure employed, which is equal to a head of six The gas produced from any generator is not inches of water. This burner, which is described quite pure, and although it is used at present in the Proceedings of the Chemical Society, 1896, more often than not without any purification, it is No. 179, gives a full working flame for ordibecoming recognised that such a course is un- nary bench operations, which, as might be exdesirable. The most important impurities in the pected, is exceedingly hot, enabling heating gas are phosphoretted hydrogen, ammonia and operations to be carried on in very little more than benzene; the two former may be attributed directly half the time that is required when coal gas is to the carbide, and although they will be very used. For ordinary flame and spectroscopic resmall in amount in the case of a good carbide, actions it is excellent, and the use of the blowpipe such as that from Foyers, their removal is very can be dispensed with for a great many small
operations. For example, a few grams of zinc, rapidly. The gas can be used with the blowpipe, if heated for five minutes in a covered crucible, and here, of course, any apparatus used for coal will take fire and burn readily on the removal of gas is applicable, since the air supply can be regu. the crucible lid. Naturally this heat has its dis- lated at will. With a powerful air-supply the advantages for some purposes, particularly in acetylene blowpipe becomes a most valuable necessitating additional care in bringing glass weapon for producing very high temperatures, apparatus into the flame. Jena glass stands well, and if oxygen be used instead of air, the heat is of course, and a good Bohemian beaker or flask, probably only rivalled by the electric arc. Steel with its contained liquid, may generally be ex- may be readily melted, and we can cite an inposed to the flame with impunity, but thicker stance in which a hole was melted through a German-glass vessels are very liable to crack on small London - clay crucible of very reputable sudden exposure to the fame. The flame cannot make, when oxygen was used. be turned down low without becoming luminous Taking the advantages and disadvantages of when the Bunsen is adjusted to give a non- the gas for the laboratory bench together, there is luminous flame of good size, though small non-lumi- no question as to the pre-eminence of the former. nous flames may be obtained by adjustment of Certainly the laboratory which, we believe, has the burner for this purpose alone, and this under had the longest experience of this use of the gas so small a pressure as three inches of water. This would not now make an exchange in favour of luminosity, on turning down the sull-sized burner, coal gas. Perfection is yet to be attained, it is enables a collar to be dispensed with, since for true, and we look to the manufacturers of carbide blowpipe work the luminous zone appears of itself to supply the means for improvement by enabling when the flame is lowered, but for all other us to dilute the gas a little from the start. reasons it is a disadvantage. Moreover, if the jet is enlarged or filled up to any extent, this luminosity may appear in the full flame. The jets do
THE TEACHING OF HISTORY AND
GEOGRAPHY IN PRUSSIA.
By A. HARGREAVES.
Realschule, Waldkirch, Baden.
I Language Teaching in Prussia." in the Sep
tember, 1901, issue of The School WORLD, the syllabus for history and geography may with advantage be described. The time devoted to
history is about the same in all kinds of schools, Various burners for use with acetylene.
and ranges from two to three hours a week over a
seven-years' course. In the two years preceding want occasional adjustment with a fine probe or
this course, one hour is devoted to stories from a light hammer, but it is not found in practice
German history and the Sagas from the oldest that this occurs sufficiently often to form a serious
Greek and Latin history. From this point the disadvantage.
syllabus is as follows:The various modifications of the Bunsen are
History. not easy to imitate for acetylene, and the styles of the various burner-tops used for coal gas are quite
IV. 2-3 hours weekly.—Greek history to the useless. The acetylene Bunsen referred to is, death of Alexander the Great: Roman history however, furnished with a welt on which suitable to the death of Augustus. The period previous tops may rest; these consist at present of an to Solon's death on the one hand and the attachment to produce a fish-tail flame, and one war with Pyrrhus on the other is treated as to give a ring of small points for evaporations. A
A shortly as possible (this in consequence of the similar burner to the last, but one in which the preliminary work already mentioned). The most points lie in a straight line also, exists. Very important points about the cultured Eastern powerful combinations of several burners on the nations are touched upon in connection with same stand may be made. A six-jet burner suit- Greek history. A detailed description of the able for heating a small muffle-furnace is shown, encounters between the Romans and Germans together with the above forms, in the photograph during the Republic is deferred till the next class. which illustrates this article. One advantage The most important dates are learnt. which such multiple burners have over those for
Lower IIIrd. 2 hours weekly.—The golden age coal gas is that they can, owing to the small con- of the Roman Empire under the great emperors. sumption of gas, be used off ordinary bench German history from the first encounter of the fittings with ordinary quarter-inch tubing:
Germans with the Romans till the end of the Glass working, especially with potash glass, is middle ages. The history of other countries is considerably facilitated by the use of acetylene, treated as far as is neceesary for a proper underbut the flame tends to promote devitrification very standing of German history. . Dates as in IV. Repetition of ancient history based on the dates returns covering the ground more fully. The learnt.
whole period of German history has been treated Upper IIIrd. 2 hours weekly.-German history when the scholar has passed the lower IInd., after from the end of the middle ages till the begin which many of the scholars leave. ning of the reign of Frederick the Great, with METHOD.-(1) The object of the preliminary special reference to Brandenburg. Prussian history. | instruction in the first two classes is to present Foreign history is touched upon where necessary the great heroes of the past to the heart and for a proper understanding of the main subject. mind of the young scholar, in that way to develop Dates as in IV. Repetition according to the dates his thoughts, and together with the stories from learnt.
the Bible, to lay the foundation for historical Lower IInd. 2 hours weekly.German and perception and observation. The enthusiasm of Prussian history from the beginning of the reign the teacher and a sympathetic and vivid descripof Frederick the Great to the present day. Foreign tion of the heroes are the chief factors at this history as in Upper IIIrd.
stage. A special course is not adopted, but it is Frederick the Great, the French Revolution, important that the prose and poetry of the German Napoleon I. (especially his relations to Germany), reading book should stand in close relationship the fall and rise of Prussia, the wars of freedom with the biographies. (Befreiungskriege), the internal changes in Prussia, (2) For the other classes the great thing is to the re-arrangement of the political relations of distinguish the instruction in IV. to Lower IInd. Germany in 1815, the German Customs Union, from that of the upper classes. For the former the striving for political unity, the deeds of Kaiser the acquisition of the chief facts, especially with William I., and the founding of the German reference to prominent persons and the chronoempire are to form the chief part of the syllabus logical order of events, are of primary importance; for this year. In connection with the German while, for the upper classes, stress is laid on the history and the lives of the various rulers, a com- development and comparison, from different points parison is to be drawn of the social, political and of view, of the matter already learnt. Even in commercial development up to the end of the the upper class the presentation of facts and their eighteenth century, giving prominence to the retention in the memory are not neglected, but deeds of the Hohenzollerns, especially with regard together with outward events weight is laid on to the elevating of the peasant, middle and the internal relations, which naturally cannot be working classes. Repetition of the Branden- touched upon in the lower classes. Above all, burg-Prussian history according to the dates the utmost importance is at this stage given to learnt.
developing the capability of interpreting the Upper IInd. 3
hours weekly.—Chief events of present from the facts of the past, and of getting Greek history up to the death of Alexander the a clear idea of the relationship of the events to Great, and of Roman history up to the death of one another. Inducement is given to the scholars Augustus, touching lightly upon the East. Special to esteem sufficiently such events in the mental regard is to be paid to the political, social, and and industrial life of the people which have had civil relations which are to be grouped and com- an influence on their development. pared. Repetition from German history according (3) Success depends chiefly on the personal to dates to be learnt.
qualities of the teacher, which only come into Lower Ist.-The Roman emperors who had operation where the matter is freely treated and most influence on the world's culture. German freely presented to the class. history to the end of the Thirty Years War, with Great tact and prudence are required in the a deeper study of the political, social and civil selection and treatment of social and industrial relations. General idea of the rise of the states questions (Lower IInd and Upper Ist). The from 1648. Foreign relations which are of im- justice of many of the present social demands is to portance in the world's history, the Crusades, the be conceded, but the evil of all forcible attempts movements for reform in the Church, the dis- to change the social order is to be made clear. coveries of the fifteenth and sixteenth centuries, The efforts of the ruling line on behalf of the are to be treated from more general points of view people are presented wherever the history of the than in the IIIrd. Repetitions from ancient last hundred years offers an inducement to touch history according to dates learnt.
upon the social and political measures of other Upper Ist.— The most important events of European States. modern times, especially of Prussian-German his- (4) The grouping of historical facts comparatively tory from the end of the Thirty Years War up to and from different points of view is recommended, the present time. In connection with the lives of especially for the repetitions, which are carried out the great Elector Frederick William I., Frederick in all classes to confirm the matter already learnt William the Great, Frederick William III., and by heart without overburdening the scholars with Kaiser William I., comparative studies as in the unnecessary ballast in the way of dates. Books lower IInd., but correspondingly deeper.
which present history in a connected form, an atlas, Thus we see that, contrary to the practice in and a date book are used in classes IV. to Upper English schools, the teaching begins with ancient Ist. Free, connected descriptions by the scholars history and then goes on to older German history, of what has already been learnt are practised gradually working up to modern times, whence it wherever possible.
allowed. The scholars confine themselves to
simple sketches during the time of instruction, The general aim is the acquisition of an in the teacher himself first draws the sketches on the telligent understanding of surrounding nature and board. of maps, knowledge of the physical form of the (5) The teaching is in the hands of teachers earth, of the divisions of the inhabitants, and some who have made a special study of geography and knowledge of the principles of mathematical geo- is not divided among too many teachers. The graphy. The syllabus is as follows:
repetitions in the upper classes of gymnasia, so far VI. 2 hours weekly.- Principles of general geo- as physical and political geography are concerned, graphy with reference to the immediate neighbour- are in the hands of the teacher of history, the hood. Introduction to globes and maps. Elements mathematical geography in the hands of the of a knowledge of countries, beginning with the teacher of mathematics or physics. home and Europe. Books are not allowed.
The Emperor has several times insisted on the V. 2 hours weekly.--Countries of middle Europe, great importance of placing the teaching in the especially the German Empire. A book is used. hands of properly qualified men. At most univerFurther instruction with reference to the globe sities there are now professors of geography, and and maps as well as of reliefs. Simple sketches on this branch may be taken as an optional subject the blackboard.
by the students at their examinations. IV. 2 hours weekly.-Europe except the German Empire. Simple sketches on the board and in
Lower IIIrd. 1-2 hours weekly.--Countries out of Europe. German colonies : comparisons with the EXPERIMENTS IN MECHANICS." colonies of other lands. Sketches as in IV.
By W. W. F. PULLEN, M.I.M.E., Wh. Sc. Upper IIIrd. 1-2 hours weekly.--Repetition of
South-Western Polytechnic, Chelsea. German Empire. Sketches as in IV.
Lower IInd. 1-2 hours weekly.-Repetition of ExperimenT WITH THE Five-Rope Pulley European countries except German Empire.
Block. Elements of mathematical geography. Sketch BJECT OF EXPERIMENT:-To determaps as in IV. In the “Realschulen” the most
mine (1) The velocity ratio of the machine. important commercial and traffic routes of the
(2) The general relations between the load present time.
and (a) driving force, (6) friction, (c) mechanical Upper IInd.-Upper Ist. 1 hour weekly. -Repeti- advantage and (d) mechanical efficiency, tion and principles of physical geography. Elements
Method :-It will be found of mathematical geography correlated with the
very convenient to use the instruction in mathematics or physics.
vertical post in Fig. 6, to METHOD.-(1) The practical utility of the sub
aid in determining the veloject must be kept in view throughout. Physical
city ratio by experiment. Of geography is not given the preference over political,
with the simple both are united as closely as possible in dealing
machine, it is an easy matwith the different countries. Intelligent observa
ter to calculate the velocity tion of the surrounding country as well as of reliefs
ratio, but as the experiand maps is brought into play, committing to
mental method is interesting memory whatever is considered necessary. Only
and useful, it is given here a few round comparative numbers are to be learnt
in connection with the simby heart.
ple machine. The vertical (2) The first steps in physical and mathematical
post is made from a couple geography are confined to the neighbourhood of
of strips of wood, separated the school. When general principles have been
by a distance piece at each understood they are represented by reliefs and the
end, forming a long slot in globe. The use of the map is then learnt gradually
which the horizontal pointers by the pupil. The wall map and atlas are later
P and N can be adjusted by on the chief objects in class teaching Books only
thumb nuts. A small weight serve as guides for preparation at home. Great
of (say) 14 lbs. is susattention is given to the correct pronunciation of
pended from the load proper names.
hook and another weight (3) In the lower and middle classes the same
(say 7 lbs.) suspended from atlas is used. Large atlases are not allowed in
the spring-balance hook. These weights should the lower classes. Care is taken to see that the
be such that they will remain in any position in wall maps agree as much as possible with the
which they may be placed. Begin by moving the atlases.
spring-balance end downwards so that the weight (4) Great importance is given to sketch drawing 3 lbs. is as near as possible to the floor but does not as an auxiliary to clear representation, but outline
touch it. While in this position, set the upper sketches and profiles on the board are alone expected. Map drawing at home is in general not
Concluded from p. 403, November, 1901.