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while Mr. Fletcher, paymaster, and Dr. Simpson are collecting the insects and land plants. I may say at once that the latter are of the type which one would expect to find on purely oceanic islands, but their distribution from island to island is interesting, as well as their preferences for sand or rock, drought or moisture, &c., most of the islands having definite zones with their peculiar plants.
"It is really as yet too early to say anything about the reefs here, as there are one or two places which I have not yet been able to visit. What strikes one, however, very forcibly is the comparative absence of life on them. Of course there are in places plenty of corals, but the number of species is quite limited. There is a fair number of the usual Alcyonaria, but Sponges, Hydroids, and Tunicates are very few in species and in quantity. Turbellaria are very rare, while Molluscs, Echinoderms, and Crustacea are few in species and, except certain common forms, not numerous. Ptychodera we have obtained, as well as a few Sipunculids, but Amphioxus and Thalassema we have not found. At Minikoi in two tides I have brought to the camp as great a variety of animals as Cooper and I have obtained here working ten tides up to the present. Indeed, life here is strictly limited in variety, and, when the marine collections have been fully worked up, one is inclined to anticipate, even so early, that some definite light will be thrown on the distance to which the larvæ of marine animals can cross the open ocean, on the distribution, in fact, of marine animals. The same, too, is true as well of the marine plants, nullipores alone being
"I am now endeavouring to work up the physical conditions of the atoll so as to find, if possible, whether there is any physical cause for the comparative paucity of freeliving animals. I am sending Cooper in the ship tomorrow to Diego Garcia, where he will have four or five days while she is coaling to examine the land and reefs. I remain here, but I hope by the time of his return, in about twelve days, to have finished my work and to move on to Peros Banhos, while the Sealark is sounding between the banks and round the Chagos Archipelago.'
The Problem of the Random Walk.
I HAVE to thank several correspondents for assistance in this matter. Mr. G. J. Bennett finds that my case of n=3 can really be solved by elliptic integrals, and, of course, Lord Rayleigh's solution for n very large is most valuable, and may very probably suffice for the purposes I have immediately in view. I ought to have known it, but my reading of late years has drifted into other channels, and one does not expect to find the first stage in a biometric problem provided in a memoir on sound. From the purely mathematical standpoint, it would still be very interesting to have a solution for n comparatively small. The sections through the axis of Lord Rayleigh's frequency surface for n large are simply the 66 cocked hat or normal curve of errors type; for n=2 or 3 they do not resemble this form at all. For n=2, for example, the sections are of the form of a double U, thus UU, the whole being symmetrical about the centre vertical corresponding to r=0, but each U itself being asymmetrical. The system has three vertical asymptotes. It would be interesting to see how the multiplicity of types for n small passes over into the normal curve of errors when n is made large.
The lesson of Lord Rayleigh's solution is that in open country the most probable place to find a drunken man who is at all capable of keeping on his feet is somewhere near his starting point! KARL PEARSON.
Proposed Magnetic and Allied Observations during the Total Solar Eclipse on August 30 IN response to my appeal for simultaneous magnetic and allied observations during the coming total solar eclipse, cooperative work will be conducted at stations distributed practically along the entire belt of totality and also at outside stations, nearly every civilised nation participating.
These observations will afford a splendid opportunity for further testing the results already obtained. All those
who are able to cooperate are invited to participate in this important work.
The scheme of work proposed embraces the following: (1) Simultaneous magnetic observations of any or all of the elements according to instruments at the observer's disposal, every minute from August 29, 22h., to August 30, 4h., Greenwich mean astronomical time.
[To ensure the highest degree of accuracy attainable. the observer should begin work early enough to have everything in complete readiness in proper time. See precautions taken in previous eclipse work as explained in the journal Terrestrial Magnetism (vol. v., p. 146, and vol. vii., p. 16). It is essential, as shown by past experience, that the same observer make the readings throughout the entire interval.]
(2) At magnetic observatories, all necessary precautions should be taken so that the self-recording instruments will be in good operation, not only during the proposed interval. but also for some time before and after, and eye readings should be taken in addition wherever it be convenient.
[It is recommended that, in general, the magnetographs be run on the usual speed throughout the interval, and that, if a change in the recording speed be made, every precaution possible be taken to guard against instrumental changes likely to affect the continuity of the base lines.] (3) Atmospheric electricity observations should be made to the extent possible by the observer's equipment and personnel at his disposal.
(4) Meteorological observations in accordance with the observer's equipment should be made at convenient periods (as short as possible) throughout the interval. It is suggested that, at least, temperatures be read every fifth minute (directly after the magnetic reading for that minute).
(5) Observers in the belt of totality are requested to take the magnetic reading every fifteen seconds during the time of totality, and to read temperatures as frequently as possible.
(6) At those stations where the normal diurnal variation cannot be obtained from self-recording instruments, it is desirable to make the necessary observations for this purpose on as many days as possible before and after the day of the eclipse, and to extend the interval of observations given above if conditions permit. In general, those who will have self-recording instruments have decided to run them for at least eight days before and after the day of the eclipse.
It is hoped that observers will send full reports of their work to me as soon as possible for incorporation in the complete monograph on this subject to be published by the Carnegie Institution of Washington.
L. A. BAFR. Department Terrestrial Magnetism, Carnegie Institution, Washington, D.C., July 15.
British Fruit Growing.
IN your remarks on p. 297 (July 27) on the above subject, you mention "the diversity of yield from farms in the same neighbourhood... due presumably to differences of shelter and aspect.' It is a remarkable thing that, so far as I know, nothing has ever been done to find out and publish the most suitable localities, as regards soil and climate, for orchard planting. It is a question of very great complexity, and can only be dealt with properly by officials appointed for that purpose; but its importance in fruit culture is so cbvious that a considerable expenditure would be well repaid. Few people have any idea of the great climatic differences in localities within even a few hundreds of vards!
This house is on the south slope of the long range of Lower Greensand hills which runs parallel with the Chalk range the whole length of Kent from west to east. Ar this point the slope rises steeply from 200 feet above sea-level to 500 feet, my house being about 350 feet. I have carefully observed the effects of frost, &c., for the last six years, and it appears to me that the variations in temperature in the vertical limits mentioned are much greater than would be expected. Up to the 400-feet contour line the climate is singularly equable, which is preved not only by daily thermometrical observations, but by the
fact that such tender plants as Cistus purpurcus, Lam., Cheiranthus mutabilis, L'Hérit., and many others have survived the last six winters unprotected; while large bushes of Laurustinus, Euonymus japonicus, bay, &c., were evidently little, if at all, injured by the terrible winter of 1895. Yet, even within the limits of my own grounds, with a rise of only 35 feet up to the 400-feet contour line, there is a marked difference of climate. November 27, 1904, in the upper part of the garden, dahlias planted within feet of a high wall facing south were blackened by frost, while in the lower garden those in the open border were uninjured.
The difference between the climate of this place and the Public Gardens at Maidstone is fairly shown by the following comparative statement, the temperatures from the latter having been taken when I chanced to pass the place where they are put up, and therefore not selected :
Range in shade
The maxima in both cases are those of the previous day. Maidstone is seven miles from here, and lies in the valley of the Medway.
Yet, in spite of the fact that the thermometer, even on the grass, has not been below 32° since April 3, we are no better off for apples than our neighbours! The apples did not begin to flower until the end of April, so some other cause than frost must be found to account for the bad crop. This is an example of the difficulties of the question; other complications are the nature, mechanical and chemical, of the soil; period of blooming of different varieties of the same fruit; shelter from the generally prevailing cold winds in spring, &c. Still, some effort should be made to ascertain the conditions under which, on an average of years, the best crops can be obtained, and so avoid the waste of time, money, and land that has been incurred in hundreds of instances by planting orchards in unsuitable localities, while hundreds of acres of suitable land are used for corn and other crops that would grow as well elsewhere. Ulcombe Place, near Maidstone.
ALFRED O. WALKER.
Islands for Weather Forecasting Purposes.
IN NATURE for June 1 is a very suggestive article by Dr. Lockyer under the above heading, in which specific reference is made to the meteorology of Western Australia. It is becoming increasingly evident that the Indian Ocean and its neighbouring continents form one of the most interesting fields in the world for the study of meteorology, and as the officer-in-charge of an important section of this region I am most anxious to assist in this study in any way possible. Our progress will be slow if we start with incorrect theories, and my present object is to point out the probable inaccuracy of a few of the fundamental concepts, and to indicate briefly a few of the observed facts which seem to have a bearing upon the whole matter.
There is little or no rain in Perth of a monsoonal character. The wettest months are May, June, July, and August, during which time the prevailing winds are not from the S. or S.W. Rain is almost always associated with the passage of a "low along the south coast, setting in with the wind at N. or N.W., and finishing when the wind veers to S.W. and S.
There is a tendency throughout the year for the winds to alternate from the eastward during the forenoon to the S. or S.W. in the afternoon. This is most marked in the summer months, when the prevailing feature of the weather 1 Vet severe frost with great damage to crops in the Dartford, Rochester, and Ho districts; also at Maidstone and Sevenoaks on May 22-3, is reported in the Kent Messenger of Mav 27.
map is a high stretching along the ocean south of
our coastline. How far south or west this extends I
During the summer months, January, February, and March, there is a class of storm which strikes our N.W. coast and then travels across the State in a S. or S.S.E. direction, emerging in the Great Australian Bight, and travelling thence in an E.S.E. or S.E. direction towards Tasmania. Before striking the N.W. coast it can sometimes be traced from the extreme north of the State moving towards the S.W., down the coast, but keeping well out to sea, then gradually recurving, and striking the coast about lat. 20°. The existence of this class of storm and its approximate path is now beyond doubt, though until recently it was ignored in practical Australian meteorology. I think, however, it would now be safe to say that it dominates the weather of at least the western and southern portions of Australia during the summer months, though on account of the paucity of stations in its track our knowledge of the various conditions is at present elementary. It is important to bear in mind that the study of Western Australian meteorology is in its infancy. Not until the last few years was the importance of this class of disturbance recognised, and therefore any theories which had been formed require to be modified. During the last two years evidence seems to me to be accumulating that this particular class of storm persists throughout the year, and is, in fact, the dominating influence in Australian meteorology. If this be so, it can easily be seen how profoundly older theories are affected, and how necessary it becomes to make a fresh start.
and the storm centre invariably passes to the south of that
to have a considerable southerly component of motion. Only a few days ago, for instance, a disturbance struck the N.W. coast in about lat. 20°, and travelled in a S.E. direction across the State, giving rain just along the fringe of our most eastern settlements, probably much heavier in the interior desert, and causing a heavy downpour in South Australia from the centre to the south coast. Again on May 20 a disturbance approached the N.W. cape, causing rain there, next day being definitely located in the ocean a little to the S.W. of Perth, and certainly considerably north of Cape Leeuwin, then continued to travel down the coast, rounded the Leeuwin, and behaved thenceforward just like any other winter disturbance.
committee commenced to take evidence on November 8, 1904, and finished on February 17 of this year. More is heard about the loss of the synthetic colour trade to the country than about the loss of any other industry, or about the failure to establish new industries which flourish on Continental or American soil. The loss of the coal-tar colour industry is variously ascribed to incompetence on the part of our manufacturers and their failure to realise the importance of employing-and paying for-highly trained scien tific chemists, to our patent laws, to trade protection abroad, and to the excessive duty charged upon alcohol in this country. The report with which we are at present dealing has to do with the last question -duty-free alcohol. A careful perusal of the ques tions to and the answers of the witnesses before the commission, which included most of the well-known names in the coal-tar colour industry in this country, does not convince one that this special industry has been lost to the country owing to the high cost of alcohol.
The amount of alcohol used at the present day for preparing the dyes is not very large. At one time many of the dyes were sold as alcoholic extracts, and alcohol was somewhat largely used in the preparation of the products. Since the introduction of the azo There is, therefore, plenty of evidence that "lows" do dyes, however, alcohol is not nearly so largely emtravel down the Indian Ocean, even in the winter months, ployed as formerly. There are, indeed, certain dyes in a southerly or S.E. direction towards Cape Leeuwin, in which the methyl or ethyl radical is introduced and probably all, or nearly all, of our storms come in this during the process of manufacture, and these require way. If this be so, the charts on p. 111 are misleading. Our rain certainly does not come mainly with a S.W. or the employment of methyl or ethyl alcohol in their S. wind, nor is there (probably) any stationary "high" preparation, and, of course, in this case the alcohol as marked. Instead there is a series of "highs cannot be recovered; for example, the dyes in moving towards our west coast, broken up by a series of " lows, which dimethyl aniline is the starting product. which pass between and make for the extreme S.W. corner British manufacturers who desire to make these of Australia. The weather which we specially desire to colours import all the dimethyl or diethyl aniline predict comes with these "lows.' Several things follow from abroad. It came out, however, in the evidence from this. One is that the Amsterdam and St. Paul that one large aniline dye company which desired to Islands are far too much to the southward to be of any manufacture dimethyl aniline obtained Government use to us for practical forecasting purposes, though a few sanction to employ methyl alcohol mixed with oneyears' records from there would be exceedingly valuable. twentieth of 1 per cent. of mineral naphtha-“ a conAnother is that Dr. Lockyer's theory about the S.E. trades dition which the company stated would suit their purand S.W. monsoon requires some modification, though it is very probable that the Indian Although from the evidence before the composes. and Australian weathers are inter-dependent and require to be studied mission it appeared that there was "a substantial together. A third is that Sir John Eliot's proposal for profit to be made upon the manufacture of dimethyl an Empire study of meteorology ought to be acted upon aniline, for some reason or other it was never as soon as possible, and all our observations coordinated manufactured. to some definite purpose. A fourth is that, failing this, Australian meteorologists ought to make every effort to bring about the establishment of a central Australian bureau for the study of scientific meteorology, as recommended at the recent conference held in Adelaide. W. ERNEST COOKE. Perth Observatory, Western Australia, July 3.
OW far the trade in synthetic colours and fine chemicals has been lost to the country through the heavy customs restrictions placed upon the use of alcohol is a question which has been agitating manufacturers for many years past. On the one hand, we are told that the entire chemical trade has been diverted from our shores because of the high cost of alcohol; on the other, that the alcohol question has very little to do with the matter. After the agitation for the use of duty-free alcohol had been going on for some years, and owing to its increasing intensity and to the pertinacity of a few, the Government in the autumn of last year appointed a departmental committee to take evidence in order to find out whether the high duty on alcohol really was the factor which caused the practical extinction of the aniline dye industry and accounted for our inability to found an industry in fine synthetical products. The
Reviewing the evidence of the different persons connected with the coal-tar dye industry, one is brought to the conclusion that, although the high price of alcohol has militated against the success of the industry, yet there are other even more potent factors which have prevented the industry being successful. Manufacturers, with a few isolated exceptions, have not even been successful in meeting Continental competition in dyes which do not require the use of alcohol. Prof. Green probably came very close to the truth when he said, in reply to a question as to what he considered the cause of the decline of the coal-tar colour industry :
"They (the manufacturers) did not realise the great importance of research; the great importance of theory. They expected to see an immediate result from experiments, and if they did not get an immediate result they considered that they were wasting their money. They did not employ a sufficient number of research chemists, and they did not pay those research chemists they had to encourage them to remain. . . . There may be other contributory causes, such as the patent laws and this question of the spirit.
There seems to be a strong consensus of opinion that in the xylonite and gunpowder manufactory leave to use pure alcohol is much to be desired. Xylonite when made with methylated spirit is inclined to darken, and there is thus a difficulty in
making materials which should be white or ivory coloured.
interest of any chemist in yet; but they are a very great disadvantage."
Those connected with the motor-car industry and the use of alcohol for motor engines in place of petrol seemed to consider that very much better results can be obtained with pure alcohol than with methylated spirit. A perusal of the evidence leads to the conclusion that further experimenting in this direction would be advisable. One is certainly inclined to the opinion that the presence of bases would be harmful, as these would probably on combustion be converted into products which would corrode the metal work. Of course, if alcohol is to be employed for motor purposes it would of necessity require to be denatured, because it would then be sold in large and small quantities at every little oil-shop in the kingdom. If
will have to experiment with all sorts of denaturants, and, doubtless, the excise authorities would aid them in their endeavours.
In the gunpowder manufactory, if pure alcohol were used to dehydrate the material the dangerous drying process by heat could be done away with, because the material moistened with alcohol can be directly placed in the mixers containing acetone, &c., the moistness due to alcohol not interfering with the process of manufacture, whereas that due to water is harmful. For making so-called "condensed " powders which are totally dissolved in the solvent the action of methylated spirit is objectionable; as one of the witnesses stated, you cannot control the surface of the grain with a methylatedether mixture in the same way that you can with a pure alcohol-ether." To a large extent the lack of initiative on the part of British powder manufac-motor-engineers wish to build alcohol engines they turers may be indirectly attributed to the high cost of alcohol. Some lacquer manufacturers and users of lacquers state that lacquers made from pure alcohol are very much superior to those made from methylated spirit. Mr. Bagley, the witness trom Messrs. Samuel Heath and Sons, the largest brass-founders in the world, stated that, although they are easily able to compete with Continental manufacturers so far as their brass ware is concerned, their goods are often not acceptable because of the want of durability and finish of the lacquering. The lacquer costs something about 45. per gallon, but they can, by paying 325., obtain a lacquer made with absolute alcohol, and this is as good as the best foreign lacquer. The witness said he was ashamed to have to confess that they could not obtain the fine finish which the Germans produced, and, as regards the French importers, they absolutely refused to take lacquered articles, but bought them unlacquered and finished them themselves. This witness was of the opinion that the foreign lacquers were made with pure alcohol, but it was subsequently pointed out by the chairman that even abroad it was denatured. On the other hand, Mr. Gardiner, the manager of the firm of Messrs. A. Lambley and Sons, said that they not ly could make lacquers as good as Continental manufacturers, but that they had a large export trade and had no difficulty in meeting Continental competition; they very rarely used pure alcohol for making lacquers.
From the extremely contradictory evidence of these two witnesses it would appear that it is more matter of method or knack in the manufacture than of methylated or pure alcohol which determines the quality of the lacquers.
There seems very little doubt but that the manufacture of fine chemicals and synthetic perfumes is considerably interfered with owing to the British manufacturer not being able to use duty-free alcohol. When methylated alcohol is employed for crystallising the substances there is invariably a peculiar and disagreeable odour attending the finished product. But if the manufacturer, in order to get over this difficulty, employs duty-paid absolute alcohol, the increased cost of manufacture is prohibitive. It was stated in evidence, for example, that with regard to the manufacture of phenacetin "the duty on the spirit would come to 140l. on 100l. worth of the article as imported."
Chloral hydrate is another substance which cannot profitably be made in this country. In the manufacture of ether from methylated spirit Mr. David Howard stated that "if we might have pure methyl alcohol and pure ethyl alcohol, it would be a beautiful thing to make ether of. But the result of the ketones and other bodies in it is that the sulphuric acid gets in a most horrible mess, and we get abominable compounds which I have never been able to excite the
In reading through the report one is struck by the repeated reference which is made to the relative cost of pure duty-free alcohol in the United Kingdom and in Germany; British manufacturers do not seem able to compete in the manufacture of alcohol with their German rivals even when working under equal conditions. Further, it is a well-known fact amongst chemists that it is practically impossible to get really good absolute alcohol of British manufacture. It is a remarkable fact that traces of impurities which one can barely find by analysis interfere very much with the smooth working of reactions in which alcohol is employed. This fact came out again and again in the evidence of witnesses before the committee. Those on the committee who were there to look after the interests of the excise endeavoured with great skill to shake the evidence on this point, explaining that if the quantity of an impurity was only a fraction of a per cent., it surely could not possibly cause all the mischief attributed to it. The invariable reply was, the product when made with absolute alcohol has such and such properties, but it is either impossible or a matter of extreme difficulty to obtain the same results with methylated spirit.
On the other hand, in a good many cases it appeared that sufficient experimental work had not been tried. Methylated spirit had been condemned for manufacturing this or that article, but little or no attempt seemed to have been made to try spirit denatured in other ways or to try the use of other solvents. By the Act of 1902 manufacturers were allowed to suggest other means of denaturing the alcohol, and in some cases at least the excise authorities had been very willing to aid them in their efforts. matter of fact, in manufacturing operations in Germany it is rare for absolute alcohol to be employed, the alcohol generally being denatured in a way which suits the particular manufacturer. Of course, where the use of pure alcohol is absolutely necessary the German has a much lower excise duty to compete with than the British manufacturer. That excise restrictions, the high duty on alcohol, and a considerable amount of red tape have, in some cases, made the manufacture of certain products-so as to compete with the foreign manufacturer-almost an impossibility there can be no doubt. But why that should hinder British manufacturers who manufacture products in which alcohol is not employed it is not easy to see.
If instead of calling in an outside "expert" (?) when an emergency arises the manufacturers were to employ a certain number of well-trained chemists, men who, after being on the staff for a short time, should be far and away superior to outside experts, there is but little doubt that fewer emergencies
So if we are to compete with foreign competition no process should be worked year after year by rule of thumb, otherwise manufacturers will find their product being pushed out of the market by a similar but improved product in which the brain has been the motive power for the thumb.
It is very much to be hoped that now that the matter has been thoroughly threshed out the Government will step in and-while safeguarding its own interests and the sobriety of the workers-it will aid manufacturers by all means in its power by enabling them to use a class
of alcohol which will be suitable to their special needs.
F. MOLLWO PERKIN.
THE GEOLOGY OF
SOUTH AFRICA.1 OWARDS the end of last century it appeared as if England had lost her well earned supremacy in geological research in Africa. In Germany, elaborate treatises dealing sometimes with her own African colonies exclusively, and sometimes with that of neighbouring British territory, monthly and almost weekly appeared. French geologists, too, produced essay after essay on their African colonies and possessions. Meanwhile, England was apparently content to lag behind.
It is fitting that the visit of the British Association to one of our most famous and most remote African colonies this year should witness the publication of two geological works, of the highest scientific standing, written by our own countrymen. Early this
ample recognition is given to A. G. Bain, the father of South African geology, and also to Stow. More recent workers cannot complain that their investigations have been neglected.
The book is divided into five parts. Part i. deals with the pre-Karroo rocks, in which those of southern Cape Colony are described in section i., and those of northern Cape Colony, the Transvaal, &c., in section ii. This separation into sections becomes necessary owing to the want of similarity in the succession of the pre-Cape rocks in the two regions.
The authors naturally give somewhat more space to the sequence in the Transvaal, more especially to a description of the upper division of the Witwatersrand system, which includes the famous "Banket. It is interesting to find that the stratigraphical position and age of this well known deposit remain unsolved, except that the authors consider the age to be vastly newer than the Archæan rocks and greatly older than the Table Mountain Sandstone.
FIG. 1.-Contorted Band, Hospital Hill Slate, Show Yard, Johannesburg. From "The Geology of South Africa," by F. H. Hatch and G. S. Corstorphine.
year, the comprehensive treatise by Mr. A. W. Rogers on the geology of Cape Colony made its appearance. Now, a few months later, we have presented to us the philosophic résumé of the geology of South Africa as a whole by Messrs. Hatch and Corstorphine.
Both volumes supply a long-felt want. In their method and conciseness both are equally British.
In a work treating with the richly metalliferous regions of the Transvaal it might have been expected that questions of economic interest would occupy many pages. It is an agreeable surprise to find that this is not the case. On the contrary, the geology of South Africa is here described in a thoroughly scientific manner, clearly and concisely worded. All essential details are brought within a compass of 312 pages of text.
In the opening chapter, on the history of research, 1 "The Geology of South Africa." By F. H. Hatch and G. S. Corstor phine. Pp. xiv+336. (London: Macmillan and Co., Ltd., 1905) Price