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JUBILEE CATALOGUE

ISSUED TO MARK THE

MANUFACTURING CHEMISTS.

OF

THE "RYSTOS" ELECTRIC LAMP

(No. 1)

For Standing or Hanging, with Cord and
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LAMPS FOR GAS ALSO WITH BYE-PASS. New Photographic Requisite List on application. 14 COMMERCIAL STREET, LEEDS.

COLOGNE,

Contains on its more than 900 pages a complete survey of the apparatus used for instruction in Physics, as well as numerous practical instrue

tions and about 3000 illustrations.

NATURE says: The firm of Leybold Nachfolger in Cologne has recently issued a very complete and interesting catalogue of physical apparatus and fittings sold by them The book starts with a history of the instruments made in Cologne during the last century. In its second section we find an account of the construction and fittings of various chemical and physical institutions. After this follows the catalogue proper, filling some 800 large pages, profusely illustrated and admirably arranged. The book will be most useful to the teacher." (No. 1846, Vol. 71.)

THE CATALOGUE WILL BE FORWARDED TO SCHOOLS AND INSTITUTES ON APPLICATION.

IN

THURSDAY, APRIL 20, 1905.

MAN AND SCENERY.

Landscape in History and Other Essays. By Sir Archibald Geikie, F.R.S. Pp. viii+352. (London: Macmillan and Co., Ltd., 1905.) Price 8s. 6d. net. N this collection of essays Sir Archibald Geikie has given us in a connected form some of his contributions to the study of the effect of geographical environment and geological changes, not only in determining the distribution of population and of the centres of rule and of commerce, but also in influencing literature and the interpretation of history. In some of them he treats of the part man has played in controlling and directing those forces of nature which tend to produce change on the surface of the earth, and he has added a few essays dealing with subjects which arise naturally out of such inquiries. In this way he has produced a most readable book, the several parts of which hang well together.

When we have exhausted all the available documents, sought out the meaning of all the descriptive place-names and gathered the local traditions, there remains the most trustworthy evidence of all, namely, the examination of the ground to see whether the events recorded can have occurred on the area to which they have been assigned, either under present conditions or other conditions the former existence of which we can learn from what we see. Our author gives as an example the story of the Battle of Bannockburn, where the army of Edward was compelled to crowd its attack into a narrow space because Bruce had rested his left flank on what the trained eye can see must at that time have been a morass with impassable bogs and sheets of water, though it is now dry and richly cultivated.

Estuaries and the rivers which run into them provided landing places and opened up the inland regions to the vessels of primæval man, and on their banks were sites for the settlements of the first comers and the cities of later more civilised times; while, on the other hand, mountain ranges and tangled forests separated tribes and offered an insurmountable barrier to expansion and intercourse.

Man, by cutting down or burning forests, and by draining lakes and swamps, has altered the conditions of many extensive tracts of country, changing the climate, the amount of rainfall, and the rate of waste of the hill-slopes and valleys.

The south of Scotland and parts of the north of England were once covered with small shallow pans of water like Finland, "the land of a thousand lakes." Most of these have got filled up in the British Isles, and the process of reclaiming and cultivating the areas once covered with water has been hurried on by the advance of agriculture; but history tells us how the early dwellers in these broken grounds took advantage of them in their struggles against the powerful races that from age to age invaded them. The Caledonians met the Romans on such ground, and the Scotch the English in later times; and, further south, the Saxons long held their

own in the flooded fenlands against William and his Norman followers.

The mythology of Greece and of northern Europe is largely influenced by the character of the scenery in which it took shape. It was recognised that the plain of Thessaly had once been covered with a sheet of water, of which the remaining portions formed two considerable lakes. The opening of the gorge by which it was drained was attributed to Poseidon, the God of the Sea, or in later times to Hercules. Here we seem to have the tradition of an old controversy as to whether the sea, the natural operation of water running out of a lake or connected with inroads of the sea, or even artificial operations, had contributed most to bring about the draining of the

area.

The snowy summits of Olympus, rising serenely above the shifting clouds into the calm, clear, blue heaven, naturally came to be regarded as the fit abode of the gods who ruled the world, and soon Olympus came to be synonymous with heaven itself.

So, also, in the countries of western and northern Europe the grandeur and ruggedness of the scenery and the "mountain gloom" are faithfully reflected in the Teutonic myths and superstitions.

Our author gives three examples of typical districts to show how a knowledge of the causes which have brought about the varied scenery of each, far from checking the free play of fancy, enhances the pleasure derived from their contemplation.

He takes first the little cake of rock which caps Slieve League in Ireland, and leads the imagination to recall the time when it extended over all the surrounding area; but it has been removed over most of the district, a patch being left here and there to indicate the wide area over which it once extended.

Then our author takes us to the Isle of Wight, and showing us the "long backs of the bushless downs," explains how they come to rise as they do from the waves and run across the island from side to side. The long story that they tell is a stimulus to the imagination that greatly heightens the pleasure derived from the scene.

Again he carries us to the flanks of Slioch and the shores of Loch Maree, and makes them tell their tale.

He then goes on to describe the influence of scenery upon our literature. Here he is, of course, dealing with a later stage of mental development, and what he gives us is chiefly a sketch of the distinguishing physical features which inspired the descriptive passages in the poets of nature.

He tells us of the simple, child-like delight in nature which was so characteristic of Chaucer. He points out the placid rural quiet of the Colne Valley, where Milton dwelt, and which inspired the two finest lyrics in the English tongue. He describes the scenery of the Ouse near Olney and Weston, so thoroughly characteristic of the southern lowlands which filled Cowper with images of rural peacefulness and gentle beauty.

He points out how the poetry of Thomson ever showed the impress of his early life in the Scottish lowlands within sight of the Cheviot and Lammermuir Hills.

Our author is at his best when he comes to deal with the genius of Burns, to whom the hills and woods were not merely enjoyable scenes to be visited and described, but became part of his very being; who found in their changeful aspects the counterpart of his own variable moods, and whose feelings found vent in an exuberance of appreciation which had never before been heard in verse.

He touches lightly the descriptive passages in Scott and Wordsworth, and the ballad singers of the border, who, though mostly inspired by war-like achievements, often wove into their tales a thread of tender affection and romance. In the poems attributed to Ossian, although Highland scenery is not specially described, it forms a visible and changing background.

Our author turns from the consideration of the influence exerted by the geographical features of a country upon the development and habits of thought of its inhabitants to the discussion of the origin of those features themselves. This is a subject which has of recent years received much attention both in this country and in America. Our author describes the scenic features under several heads. Mountains and valleys may be considered as correlatives, the mountains being there because the valleys have been scooped out between them. Under lakes, we turn with interest to his views on the glacial erosion of rock basins, which he holds could be effected by land ice only. He makes, however, the qualifying remark that a terrestrial surface of crystalline rock, long exposed to the atmosphere or covered with vegetation and humus, may be so deeply corroded as for two or three hundred feet downward to be converted into loose detritus, and the ice may thus have had much of its work done for it, and would be mainly employed in clearing out the corroded débris. Whether, however, this will explain many of the rock basins of the British Isles is not very clear.

In another essay he shows what Hutton did by his theory of the earth to pave the way for the accurate scientific treatment of all those questions of the changes which the earth has undergone in attaining its present configuration. Playfair, Hall, and others helped on the work. The obvious question arising out of such speculations is, how long must it have taken to bring about such great results? and thus we are taken through the controversies as to whether uniform change, which we observe, or local and intermittent catastrophic action, of which we see proofs everywhere, have done most to bring about the results in every individual case. The physicists tell us that from a consideration of the rate at which the earth parts with its heat, of the limitation of the age of the sun, of the retardation of the earth's angular velocity by tidal friction, they are not prepared to allow such a vast age as geologists have claimed for the earth. The geologists, on the other hand, having regard to the rate at which changes on its surface are observed to be brought about by existing agents, and the time demanded for the evolution of living things, insist upon a much larger estimate of time than the physicists are prepared to allow. The con

fidence reposed in the accuracy of such inferences must depend upon the probability or improbability that the observer has seen enough to justify his generalisations, and that no contradictory evidence can be forthcoming.

The geologist and physicist will probably arrive at a compromise when the one admits that his calculations, based on the rate of waste, may be entirely vitiated by earth movements, which will either hurry on or retard such waste, and that life will change more rapidly with the changes of environment produced by earth movements, and when, on the other hand, the physicist has corrected his estimate of the rate at which the earth is cooling by taking more careful account of the variety of conducting material of which the earth is composed, has estimated the planetary fuel for ever being thrown into the sun from space, to say nothing of the new views of radioactivity, and has re-considered his inferences from tidal friction, which some of our highest mathematicians admit is still open to doubt.

Such speculations suggest the name of the great apostle of evolution, and an essay on the life and work of Charles Darwin follows, while a biographical sketch of Hugh Miller is fitly introduced among essays which so largely deal with the influence of a man's environment upon his imagination and writings.

In an age like this, when the relative place and value of technical and literary training are so strongly forced upon the attention of the country, an essay on science in education by one whose experience and outlook are so wide will be welcomed. Then, to bring us back to the main subject with which he commenced, he gives an interesting sketch of the building up and moulding of the Campagna and the surrounding country, fitting it for the site of many an ancient city, and at last for the eternal city so long the centre of the world.

A MAGNETIC SURVEY OF JAPAN. A Magnetic Survey of Japan reduced to the Epoch 1895.0 and the Sea Level. Carried out by order of the Earthquake Investigation Committee, reported by A. Tanakadate. Pp. xii+347 and plates. (Published by the University, Tokyo, Japan, 1904.)

THER

HE completion of the detailed magnetic survey of a country is a task requiring great skill and industry. We congratulate Prof. A. Tanakadate and his colleagues on the successful accomplishment of a heavy piece of work, which will be welcomed by all who are interested in the science of terrestrial magnetism. The work is the result of the voluntary cooperation of sixteen observers, of whom seven are professors or assistant professors of the Imperial University, Tokyo, the others also occupying responsible positions. Prof. Tanakadate modestly only claims for himself the position of a "reporter ", who has collected the work of the different parties, but we imagine that we owe to him also the detailed discussion of the results which forms an essential por tion of the volume before us.

A clear account is given in the initial paragraphs of the method of observations and the instruments used, but not too much space is devoted to these details, so that the reader is soon brought to the first difficulty which occurred in the working out of the observations. It was necessary, in order to reduce them to a common epoch, to take account of secular variations. This might most easily have been done by choosing as observing stations the same places at which the magnetic elements had been determined in a previous survey, but in attempting to carry this out it was found that the changes which had taken place in their surroundings made it impracticable to observe at most of the old stations. Some other method of reduction had therefore to be adopted. Empirical expressions were found for the magnetic elements in terms of longitude and latitude similar to those deduced by Prof. Knott for the previous survey. A comparison of the two expressions gave the secular variation. The results of all the observations for each station are given in the report. The reduction of the observations to sea level is always to some extent arbitrary. The process employed in the present case, where use is made of relations given by the theory of the potential between the radial variation of the horizontal components and the horizontal variation of vertical force, is an improvement on the more empirical methods which have sometimes been adopted.

A further application of the potential theory may serve as an important check on the accuracy of the observations. If a potential exists, the rate of variation of the northerly force towards the west must be equal to the rate of variation of the westerly force towards the north. If this relation does not hold, the

To put the matter plainly: If the magnetic forces at all points of the surface of a sphere can be represented in terms of a potential which is expressed as a series of spherical harmonics proceeding by negative powers of the radius vector, then there are no magnets or electric currents outside the sphere. If the passage quoted is intended to deny the truth of this proposition, the author is guilty of a heresy which he does not justify either by his hydrokinetic analogy or by his reference to one of Lord Kelvin's papers. It should be said, however, that in other parts of his volume the author seems to adopt Gauss's reasoning as to the discrimination between outside and inside effects by spherical harmonic analysis. It may be, therefore, that the apparent meaning of the passage is not the one which it was intended to convey. is of some importance to avoid misunderstanding on so important a matter, and it is for this reason that I feel compelled to direct attention to the only criticism which can fairly be raised with regard to a very meritorious and heavy piece of work.

It

earth's magnetism cannot be completely represented by a potential, and this would mean that vertical electric currents traverse the earth's surface. authors of the present survey calculate the intensities

of these vertical currents, but rightly do not attach

much importance to them. They are much greater than observations on atmospheric electricity allow us to contemplate as possible. We may therefore take the calculated values of these currents to be indications of the extent of uncertainty in the observations.

We must refer the reader to the original for the discussion of local disturbances, but cannot avoid directing attention to one passage, which seems to indicate some kind of misapprehension on the part

of the author.

"It is often erroneously believed," he says, "that the expansibility of the earth's magnetic potential in negative powers of the radius vector is a proof that the source of action is inside the earth."

In a preceding sentence the writer connects his supposed error with the fact that "inasmuch as the surface integral of the force over the earth vanishes, the so-called seat of action may be placed either inside or outside."

In this passage the author seems to doubt a wellestablished theorem which is quite independent of the question whether the surface integral of normal force when taken over the whole surface of the earth has a finite value or not.

WORKS written for the textile industries may be

of a

divided into three classes, viz. descriptive works more or less technical and practical character, educational works leading students up to an appreciation of the difficulties to be faced, and works which combine the descriptive and educational but which too frequently meet the requirements of neither manager nor student. The work under consideration meets the requirements of the mill manager or advanced student in a manner perhaps more than satisfactory. On the other hand, to place such a work as this in the hands of the elementary student would be anything but satisfactory, rather suppressing than developing that genuine interest without which it is impossible for the student to make true progress in his studies. In its particular line, however, we must highly commend the work as representing up-to-date practice in most of the sections of the textile industries of which it treats.

The work is really arranged in four sections, the first three chapters being devoted to general particulars respecting the fibres in question, chapters iv. to xv. dealing with the mechanical processes necessary for the formation of the said materials into satisfactory yarns, chapters xvi. and xvii. referring to

miscellaneous processes, such as the manufacture of threads, twines, cords, and ropes, while chapters xviii. to xxi. treat on general mill management, arrangement, and engineering.

In the first section, very interesting and useful particulars are supplied respecting the fibres and their marketing, the only difficulty being the grasping of the multitude of details here given. Had these details been represented by maps illustrating (a) area of growth, (b) area of manufacture, (c) area of distribution and use of the fibres in question, with graphical illustrations of quantities, &c., the facts presented would have been vastly more interesting and useful. This method, we believe, is employed in the textile museums of certain of our northern technical colleges.

The author wisely remarks in his preface that were it not for the similarity in the processes necessary for the preparation and spinning of many of the fibres here treated, it would be impossible to bring the work within reasonable limits. The similarity in treatment is certainly marked, and practically leads the author throughout to the employment of the "comparative method." Thus, in the first preparation of ramie, the hand and the chemical or mechanical methods are naturally compared with reference to quality of result and price, this latter necessarily involving the question of native handlabour versus European machine-labour. Then the difference between ramie and flax is naturally noted, and so on.

The comparative method would naturally arrange itself under some six heads :-(1) methods of dealing with the fibres in the raw state commercially; (2) methods of preparing, that is, of cleaning for the subsequent mechanical operations; (3) ultimate length, diameter, colour, &c., of the fibres; (4) the conditions for preparation of the fibres as necessarily deciding the types of machines required; (5) the types of machines for each quality of fibre; (6) value of resultant thread or fabric as revealed by scientific and “use " tests.

This is approximately the grouping employed. The greater proportion of the book is devoted to the mechanical side, and it must be recognised that this is just, as in many cases not only has the machine taken the place of the hand method, but actually does what would be impossible without mechanical aid. Perhaps one of the most interesting comparisons in the book is that afforded by chapters xii. and xiii., in which dry, semi-dry, and wet methods of spinning are successively dealt with.

The section dealing with threads, twines, ropes, &c., is chiefly interesting as introducing machines which are practically unknown in the ordinary textile industries. It very often happens that principles developed in one industry would be of great value in another were they known; in this way the present work may indirectly be of considerable use to industries other than those specially dealt with.

Chapter xviii. deals in an interesting manner with the mechanical department, including the hackle setting, wood turning, fluting, oils, and oiling; this is certainly a useful chapter for the ordinary mill

manager. Chapters xix., xx., and xxi., however, in our opinion, are somewhat out of place, it being im possible satisfactorily to consider modern mill con struction, boilers and engines, steam and water power, and electric power transmission in the fiftysix pages devoted to this subject. Mere statement. usually very excellent, is all that is possible. would, however, question the advice given respecting electric lighting in factories. There is a marked tendency to revert to incandescent gas lighting, not only on account of the expense, but also on account of the light value.

We

The work is not only to be commended to those engaged in the particular trades in question, but also to those engaged in the allied textile industries, as such questions as the position of the nip of the rollers in relation to the spindle and with reference to length of fibre, the varieties of gills employed, Combe's expansion pulley and quick change motion in place of the cones in cone drawing frames, &c., constitute interesting mechanical arrangements which may be of marked value in these allied industries.

The work is illustrated by 161 figures, usually of a most interesting type. The general arrangement is certainly such as will commend itself to the mill manager, who will naturally wish to refer to the work under conditions requiring speed and accuracy, ALDRED F. BARKER

66

probably in common with many practical foresters, tinental, or even Scotch forestry to entitle it to be that English forestry is sufficiently distinct from Conregarded as a separate subject.'

The author further emphasises this point in his chapter on thinning and pruning, where he seems to hint that all the mistakes and failures in English sylviculture, about the middle of the nineteenth cen tury, were due to the bad influence of Scotch forestry and Scotch foresters, who, according to Mr. Forbes, were imported into England about that time, bringing with them their mistaken ideas of thinning and pruning, to the detriment of English forestry.

The following extract from the preface gives the author's own views regarding the book :

"This book is intended to be suggestive rather than instructive to the practical forester. There is little in its pages but what he already knows, and possibly a great deal with which he will not agree experience it is offered as more or less faithful record of individua forestry literature, which, if it does not enrich, it wili a small contribution to not, it is hoped, disgrace."

But as a

The concluding paragraph of the preface states "that this book is not, nor does it make a pretenc of being, a text-book. The intelligent reader, there. fore, who discovers that it does not contain a planter's