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are unknown to the quaternionist. It is a suggestive fact
Suspended Germination of Seeds. that both Gibbs and Jahncke, in order to develop their re- The letter of “H. B. P.” in Nature of September 27 spective systems, found it necessary to introduce quite other
(p. 540), while giving an interesting instance of the sudden kinds of products of vectors-products which are as different
appearance of the foxglove on a bare hill in the north from one another as each is from the quaternion product,
country, does not appear to be conclusive as to the sevd. and yet have not the geometrical significance of Hamilton's
lings having developed from long-buried seeds. Thes creation.
might have originated equally well, it appears to me, fru.lt There is an idea in some minds that there is a rivalry wind-blown seeds being conveyed to a recently disturbed between vector analysis and quaternions. There is nothing soil, where they had an opportunity of germinating, and of the kind. There is a quaternion vector analysis and a
where they were not subject to the competition of other crowd of other vector analyses known best by the names of
and stronger species. On the extensive shingle depot their authors, such as Grassmann, O'Brien, Gibbs, Heavi
near Dungeness, in Kent, one of the earliest species to side, Bücherer, Jahncke, Henrici, Peano, Macfarlane, &c.,
appear on the newly deposited shingle is the foxglove. no two of whom, curiously enough, agree with one another. The first is usually
the Of all these, Hamilton's is the only vector analysis
oat-grass Arrhenatherurs avenaceum,
the third is often the wood-sage associative in its vector products. The importance of this Teucrium Scorodonia ; the seeds of all these must have associative law does not, of course, appear so long as we come from some considerable distance, and it is not sugrestrict ourselves to products of two vectors only, and, as
gested that the plants arose from long-buried seeds. a matter of fact, many vector analysts never really get to
I am by no means asserting that seeds may not under higher products. When, however, three or
suitable conditions remain dormant for considerable are to be combined, the associative law must be fulfilled
periods, but we want instances to prove this in which if simplicity and flexibility of operation are to be retained. other factors have been carefully and completely eliminaird The vector analysis which admits the associative law in
This does not appear to be the case in the above instance, product combinations is the quaternion vector analysis,
where it is also possible that the seeds produced in the however it may be disguised by arbitrary symbolism and
summer may have been blown into the interstices oi the notation.
C. G. KNOTT.
wall, the disturbance of which led to their dispersal ones Edinburgh University, September 21.
the site, and this might account for the absence of the
seedlings from the neighbouring turf-surface which had I ALSO deplore the use of the current but misleading
also been disturbed, and which should have yielded the in phraseology which Prof. Knott points out. Quite certainly had the seeds been blown from the dry capsules of the Prof Knott's more detailed statement should be substituted
plant after the destruction of the wall in the spring. in the interests of “ terminological exactitude.'
Yardley Lodge, Oxford.
G. CLARIDGE DRICE The WRITER OF THE REPORT.
The Rusting of Iron.
Has anyone inquired whether the rusting of iron mat Remarkable Rainbow Phenomena.
not be associated with some micro-organisms? The faces When I read Mr. Spence's interesting letter (p. 516), it that oxygen, water, and carbon dioxide are necessary. occurred to me that the appearance of the second primary
that iron does not rust when immersed in boiling water rainbow was due to the reflection of the sun from the sea. and then sealed up; that certain solutions are said to The apex of this second bow would be above that of the inhibit rusting (e.g. potassium ferrocyanide, a poison), and first bow, the angular distance between the apices being that certain other solutions encourage rusting R about equal to double the sun's altitude at the time of the
ammonium chloride and perhaps sea-water, compare the observation.
composition of plant-culture solutions); that iron is a Taking approximate figures, I make Deerness to be in constituent of chlorophyll, and that rusty nails sometimes longitude eleven minutes of time west of Greenwich, and cause blood-poisoning, all these facts suggest a case tot in latitude 59° north. Assuming Mr. Spence's times to be inquiry. There is, I think, an iron bacterium noted ir Greenwich times, the sun's altitude at 6h. 3om. p.m. was some of the bacteriological books. The precipitation auf about 4°, so that the angular distance between the apices iron carbonate might conceivably hold a place in the life of the bows would be about 8°, a result differing but of some organism corresponding to the precipitation of "little from Mr. Spence's estimate of 5° or 6o. As the sun calcium carbonate by foraminifera. sank this distance would diminish.
HUGH RICHARDSON I should be glad to know if Mr. Spence observed any 12 St. Mary's, York, October 1. difference in the intensity of the light. One would expect the higher bow to be the fainter of the two, as it was due
Colour Illusions. to a reflected sun, though the loss of light by reflection would be diminished by the very low altitude of the sun.
With reference to Mr. T. Terada's letter in your issum By Fresnel's formula, the reflected sunlight would be to of September 27 (p. 540), I noticed some similar efie 's the direct sunlight in the ratio of 13 to 20. If we neglect while making experiments with a form of colour top la the slight polarisation of this reflected light, these numbers year. An old gramophone motor forms a very convenient will also express the relative brightness of the higher and way to observe this, and by using various discs painted in lower bows, other conditions being alike.
different rings and segments many curious optical effects Probably the most remarkable case on record is that of may be seen. the octuple rainbow, seen in 1841, by the late Mr. Percival I was, in fact, trying to see whether the effect of the Frost, from the top of Dunstaffnage Castle, near Oban. persistence of vision could not be used to indicate the The sea, both behind and before the observer, was perfectly speed, and, to a certain extent, it can no doubt, but the smooth. Four bows were seen in the sky, viz. ordinary effect is not sufficiently definite, and there is too much of primary and secondary bows due to direct sunlight, and, the personal equation present to make it of practical us above these, primary and secondary bows due to sunlight If a disc is painted in two or more rings, and each ring -reflected from the water behind the observer.
is divided into a different number of segments, in colcurs Seen in the water in front were also four bows, inverted or black and white, it is well known that each ring * *by reflection. These bows were not images of the first become a uniform colour above a certain speed, according four, but images of four bows that could have been seen to the number of segments; the effect takes place at aba' in the sky had the water been removed and the observer forty alternations per second. Very interesting serb brought down vertically to a position as far below the scopic and complementary colour effects may be obtaine! sea-level as the actual observer was above it. The eight in this way, some of which I have not seen menticia bows formed four intersecting circles. For further details yet; the complementary colours only appear at a cers and an illustration reference should be made to NATURE, speed, and show best in sunlight; the effect is peculiar - vol. xli. (p. 316). C. T. WHITMELL. almost iridescent sometimes.
B. J. P. R Invermay, Hyde Park, Leeds, September 29.
LOWELL'S OBSERVATIONS OF THE it is well to bear in mind that the power of the PLANET MARS.1
telescope is of less importance than steadiness and I N the year 1893 the important volume on Mars, clearness of the air and keenness of the observer's
entitled “La Planète Mars et ses Conditions vision. In fact, Schiaparelli's observations of the d'Habilabilité,” was noticed in these columns (vol. canals made with his 6-inch telescope were not xlvii., p. 553). This work, the outcome of an immense corroborated at once by observers who were armed amount of labour on the part of M. Camille Flam- | with very much more powerful instruments. marion, brought together every available observation That keen-eyed observer Dawes was accustomed to ind piece of information that could be gathered from cut down the aperture of his telescope according to published 'and unpublished works. In fact, the the kind of night experienced. Thus he termed his history of the observations made on this interesting observing nights 6-inch night, 4-inch night, &c., planet was traced from the time of the earliest according to the " seeing." record (1636) down to the opposition of 1892.
In considering Mr. Lowell's observations of Mars, Fourteen years have now elapsed, numerous workers the reader must bear in mind that, unlike most astrohave been busy studying his surface markings, and nomers who make their observations from where the steady progress has been made in corroborating old observatory is permanently situated, Mr. Lowell and discovering new features. The time seems, investigated the “ seeing conditions of a great therefore, ripe for a work supplementary to that above named which should bring together the mass of valuable material which is now scattered through many different pamphlets and journals.
Such an undertaking would undoubtedly consume much time and labour on the part of the compiler, but would prove a valuable addition to the literature of planetary astronomy.
Failing such a work at the present time, we have, however, a volume which will not only fill up the gap temporarily, but will reduce to a very considerable extent the labour of the future compiler to whom reference is made above.
This very handsome and valuable publication gives a detailed account of the observations made by Mr. Percival Lowell himself during the oppositions of 1894, 1896, and 1903; the supplement to the volume contains the observations of Mr. Douglass, assisted by Mr. Drew, at the opposition of 1898, owing to Mr. Lowell's absence through illness, and of Mr. Lowell and Mr. Douglass at the 1900 opposition.
In the arrangement of the subjectmatter Mr. Lowell follows the classic memoirs of Schiaparelli, considering each opposition by itself, and adopting a chronological and topographical order for the observations themselves. In this way, during an opposition, the
Fig. 1.-Lowell's drawing of Mars at longitude 90° at the opposition of 1903, showing Solis story runs on in time while making
Lacus near the top. meanwhile the circuit of the planet."
As is well known, Mr. Lowell preserves Schia- number of regions in order to choose the most parelli's nomenclature, which he refers to as an “at efficient spot for the observation of planetary details, once appropriate and beautiful scheme." He makes, and hence the position for his observatory. The however, one important change, which is necessitated steadiness of the air at Arizona thus allowed him to in the light of advance of our knowledge of the use larger apertures efficiently, and, coupled with interpretation of the planet's markings. In the place his keen sight and expertness in this kind of observof “Lacus" he adopts the word “ Lucus,” an alter- ation, his observations are of the first importance. ation of a single letter, for markings which were | He, like Dawes, found that the aperture of the telepreviously considered to represent water are scope had to be suited to the night. Thus of the looked upon as probably oases of land. It was Mr. ; opposition of 1900-1, using a 24-inch refractor, he W. H. Pickering's observations and deductions which writes (p. 101):-first suggested this inversion of the then general idea “ Observations were made with the 24-inch objective of the dark and light shadings, and this knowledge of the observatory and usually with the full aperture was considerably extended by Mr. Lowell's observ- of the objective. On occasions, however, this was ations.
capped down to an aperture of 12 inches; an optical In the observation of details on a planet's surface device which usually improved the seeing; : . but
because by so doing the harmful effects of the air 1 - Observations of the Planet Mars, during the Oppositions of 1894, 1896, 1898, 1901 and 1903, made at Flagstaff, Arizona.” By Percival
currents were reduced. For the same reason at times Lowell. (" Annals of the Lowell Observatory," vol. iii., 1905.)
even the 6-inch could be serviceably used.”
At the opposition of 1894 an 18-inch glass made Syrtis Major, which was central on the dise, the most by Brashear was employed, but for the oppositions of prominent features were tongues of shade which las 1896 and later the 24-inch objective mentioned above between Hellas and Naochis, and nearly joined the was made and mounted for the observatory by Alvan Syrtis to the blue band bordering the cap. “For the Clark and Sons, the last glass, as it chanced, of rest no detail could be made out upon the disc, esoept that famous firm."
for two dark spots where the coast-line dipped to Even at Flagstaff Mr. Lowell was not content with enter the Great and Little Syrtes respectively; the only the astronomical conditions of seeing all the year salient points these of an otherwise featureless face. round. For this reason, at the opposition of 1896–7, Not only was there no sign of a canal, but even the he determined to try the conditions in Mexico for the main markings showed dishearteningly indefinite." winter months; observations were therefore termin- Such an apparent lack of markings was, 35 Mr. ated in November, 1896, and not resumed until Lowell points out, a matter of the Martian date.lt December 30. In the meantime the dome and tele- was, as he says, " the very nick of time to see nothing. scope were transported and set up at Tacubaya, near For the part of the planet most presented to the the city of Mexico, in latitude 19° 26' N. This earth was then at the height of its dead season." temporary change resulted in a long series of post- Mr. Lowell states, further," when we consider that opposition observations.
such is always the face the planet shows when at its With regard to the method of recording the observ- nearest to the earth, and that till lately such time
was commonly, chosen for examining its disc, it is small wonder that previous to Schiaparelli the strange canal-system should have escaped de tection.
The above extracts will, we think, convey to the reader the pitfalls into which the Martian observer stumble in consequence of the seasonal changes on the planet.
Again, Mr. Lowell gives instances of markings which undergo a secular variation covering many years. Thus a conspicuous single canal, called by Lowell Sitacus, connecting the eastern fork of the Sabaeus Sinus with the north-east corner of Aeria, was not
seen by Schiaparelli. It was such 1 Aque
salient feature in 1894 that he could calidae
not have missed it had it been there. Cerulli noticed it in 1896, and it ha:
been seen at all subsequent opposition at Alcyonida
as a fairly conspicuous canal. This sopterapie
canal exemplifies, as Mr. Lowell says, “the truth of a deduction of Schuaparelli that the canals were curious subject to secular wax and wane.
Another canal, Ulysses, unrecorded by Schiaparelli, which in 1894 . comparable in strength with the Gign or the Titan, is a further instance of secular change.
It is interesting to note that Mr 1 270°
Lowell gracefully explains the great difference between the number, 18j, of
canals seen at Flagstaff at the oppontFig. 2.- Longitude 270° at the opposition of 1991 with Syrtis Major near the centre of the disc (Lowell).
tion of 1894 and that recorded by
Schiaparelli, 79, as “due solely in ations, drawings, notes, and micrometer measures consequence of better observational conditions of in formed the usual routine. The drawings were made sort and another." on circles about 40 mm. in diameter, a convenient size Among other results of this opposition was the for combining • most satisfactorily sufficient space clear detection of the seasonal change; an increase in with possibility of keeping proportions." As a rule, the number of the oases which lie at the intersection we are told, the drawings were of the complete of the canals; an extension of the canals in the dark disc, and were made as nearly instantaneously as regions which conclusively showed that the dark areas possible.
were not “ seas "'; observations on the changes o Coming now to the observations themselves, and shades of the dark areas showing that they were nc the numerous clear drawings which accompany them, bodies of water; and, finally, peculiar marking it seems extremely difficult to refer to any particular termed“ nicks,” were observed where the canal set of them, as they are all so full of interest. The entered the light regions. observations bring out, however, very clearly the Space does not permit one to enter into an this apparent discrepancies which have arisen between like detail with reference to the observations made observations taken of the same region, but at different at the succeeding oppositions. In that of 1896 there times, by well-known Martian observers. Thus, to was sufficient evidence to show that, as Schiaparel take a case in point, in the opposition of 1894 Mr. had pointed out, the doubling of the canals was da Lowell relates how, in observing the region about wholly a seasonal effect. Another observation /
importance was the identification of a rift in the region about the Mare Acidalium and the pole, this snow-cap with the subsequent canal called Jaxartes. region being obscurely semi-white. On January 23
In the opposition of 1900 the Phosin and Euphrates Mr. Lowell wrote :-“No sharp limit to polar cap. were always seen double, as in 1896. Mr. Lowell Think it surrounded by spring cloud." suggests that probably the two epochs of gemination Many other points of interest in connection with of the canals on Mars as laid down by Schiaparelli these and similar observations might be dwelt on at may not be epochs of gemination, but epochs of some length, but the reader must be referred to the greater conspicuousness of the gemination at one volume itself for a more intimate study. time than at another; this would bring apparently In addition to a good index to the volume, there discordant facts into line.
is a special index of the names on the maps and During this opposition Solis Lacus was not seen globes. In the latter there are fifty-four regions, 392 with its usual distinctness, and it is inferred that as canals, and 172 oases mentioned, which will give the it was at its dead season it had turned sear and reader some idea of the number of Martian markings vellow. White equatorial spots of long duration were seen at Flagstaff. an important feature at this time.
In addition to the frontispiece, which is a reproThe observations of 1903 were very fruitful with duction from a photograph of the 24-inch equatorial, results, and special reference should be made to the there are thirteen plates and seventy-six illustrations relationship between the oases and the double canals. in the text, all of which are of first-class quality.
Printed in large, clear type on smooth, stout paper, and occupying about 350 pages, the volume contains a valuable increase to our knowledge of Mars, and forms a handsome addition to the astronomical library.
On the production of this volume Mr. Lowell and his staff are to be sincerely congratulated, the more so that since its publication success has rewarded their endeavours in recording the canals of Mars on a photographic plate (Roy. Soc. Proc. Ser. A, vol. Ixxvii., p. 132).
WILLIAM J. S. LOCKYER.
THE PLACE OF THE MODERN
brations of the University of
buildings Marischal 1 270°
College serves admirably to
endeavours to provide this country FIG. 3.-The same longitude (270) as in Fig. 2 from observations made at the opposition of
with institutions adequately equipped 1903 (Lowell).
to supply instruction of the highest
grade and with facilities for research The reader should also direct his attention to the in all departments of knowledge, our statesmen, our semi-annual flux in the development of the canals men of science, and our men of wealth are receiving which was revealed, showing that two waves of de- some of that encouragement of their efforts which it velopment sweep alternately over the planet's surface is the power of our Sovereigns to bestow. in the course of one of its years, this being clearly The brilliant gathering of learned men eminent in illustrated in Lowell's cartouches.
every sphere of human endeavour, and representative Regarding the appearance of cloud on the planet's alike of science, art, and letters, may be taken as surface, Mr. Lowell is inclined to think that the large, a happy augury of the unanimity that prevails to whitish marking named Hellas to the north of spare no effort in the pressing work of supplementing Syrtis Major represents either mist or cloud. In the and extending the supply of seats of the highest opposition of 1901 it was never seen as white as the learning in every part of ihe country, with a view to polar cap, although it approximated to it more than place Great Britain on terms of equality with other to all the regions outside of it. He was thus led to great nations in the keen competition which is the believe that it was not formed of snow, but of
outstanding characteristic of international relations at thing which would thus hold an intermediate position the beginning of the twentieth century. between snow and ground, namely, cloud or mist.' With these evidences of educational enthusiasm
Another, among other references to cloud, is men- and endeavour before us, it seems a fitting opportunity tioned at the opposition of 1903, in relation to the to consider briefly what appears to be the current
plan of procedure and to inquire how far this is likely these we have in a more abundant measure than is to meet the prevailing needs. Enthusiasm, unless necessary to meet present needs—but students suitwell directed, is not enough. British educational ably prepared and thoroughly grounded in the fundaendeavour has too often proved unproductive because mentals of a sound secondary education. The number of its haphazard character, and instances are extant of day students in our technical schools and college where in neighbouring countries better results have is still ridiculously small, and too many of those in followed a smaller expenditure of money and trouble, attendance are reaping little benefit, because they lack because each new development has made an addition habits of serious study and the acquaintance with to a carefully conceived plan. The policy of muddle fundamental principles they should have acquired ai is, at all events, fatal in education.
school. It is in this direction that immediate improves There must, in the first place, be an intimate con- ment is required. In Germany, to quote an example nection-a close association throughout, indeed- of what can be done, the secondary schools are turnbetween the systems of elementary and secondary ing out youths trained to think and to reason, trained education on one hand, and the colleges and universi- in the methods of acquiring knowledge, and inspirest ties on the other. The trinity of grades must form with an earnest desire to study the subjects necessar. an organic whole dominated by the same ideals, to enable them to occupy positions of command in imbued from base to apex with the same spirit of their country's industrial army. But the German bor earnest thoroughness, where at every stage the is, as a matter of course, allowed to remain at the learner must be taught to be content with nothing secondary school to the age of eighteen or nineteen. short of the best. A boy's opportunities for progress and parents willingly make the necessary sacrifice should be limited only by his natural aptitudes; and having learnt how abundant in later years is the brains, wherever found, must be regarded by educa- reward. In some way or other, if we are to comprar tional administrators in every district as a national on anything like equal terms with other nations, wt asset to be trained, developed, and sharpened to their must import a spirit of greater earnestness into our full extent. How far this is from being the case at secondary schools, allow our boys to remain in them present many recent articles in NATURE and other longer, and adjust our curriculum to modern nerds contributions to current literature have shown. Not | The British boy, if rightly directed, has no superior only is the amount of preliminary training received in ability, earnestness, and intelligence generally, and by boys seeking admittance to college insufficient, but it is little short of criminal to handicap him with an the kind of education they have received is unsuit- antiquated course of study and a curtailed schouil able.
career. The principal of the Manchester Municipal School But it is not only the bonds which connect the of Technology, who is particularly well qualified to secondary school with the university which must be speak on this subject, wrote in an article (School | drawn closer and strengthened; the systems * World, April) published this year :
elementary and secondary education must be rendend
more interdependent. Our capacity-catching mach Those who are familiar with the standards of entrance
inery has improved in recent years, it is true, but it to our advanced schools and colleges of science know only is far from perfect; and the endeavours made to op too well how low are the standards of admission. Whatever may be the 'face' requirements of matriculation, the
a way for boys of exceptional brain-power in the actual marks required for a pass are extremely low, neces
elementary school, through the secondary school. sarily so in the present state of our secondary education.
the university, have been spasmodic and not in It is further well established that the average time actually accordance with a carefully thought-out scheme. Inspent in the secondary schools is not much, if any, more
discriminate scholarship giving has in many case than a third of that required in German and Swiss schools resulted only in the manufacture of surplus clerks of similar rank-in short, either the pupils go in too late and ill-trained schoolmasters, and the absence of clear or they finish too early. In any event, they leave without aims and a definite policy as to what education in an adequate training, alike in respect of both time spent expected to accomplish for these exceptional boys haand subjects studied. Moreover, the age of admission to resulted in waste of money, loss of opportunity, and our universities and specialised schools of applied science
a growing disbelief in the efficacy of higher edura is two years below that of similar institutions on the Con
tion. Instead of benefiting our industries anc tinent. In these circumstances, how is it possible that the output, in respect of the quality of the students, can
strengthening the hands of our manufacturers, our rivál that of foreign institutions?
educational muddling has given rise to disconteni
whereas a policy of clear thinking and the applicatior Commenting upon the kind of secondary education of the methods of science to educational problem. given in this country, a writer in NATURE of March would have produced a well-balanced and judicious 23, 1905 (vol. Ixxi., p. 487), states :
graded system of national education-capable of pare
viding the country with trained workers for furn “ The custodians of English education are still actuated sphere of activity. by mediæval ideals. The entrance of the student of science to the older universities is still obstructed by an obsolete versities themselves if such a coordinated schemr "
Equally striking would be the effect on the un and ludicrous test in Greek. There is a tendency even yet education could be brought into being: instead among those in charge of our Department of Education to discourage and hamper the instruction in science in our
the glorified boarding school type which at present elementary and secondary schools."
functions as a university, where young men continu
to play games and practise “ good form " to the Lord Strathcona did well to emphasise in his exclusion of serious work, all our universities would address at the Aberdeen graduation ceremony the be institutions filled with well-trained youths earn stimulating influence which Scottish universities have intent upon acquainting themselves with the triunde had upon the schools of that country, for it is accomplished by modern research, and upon fittita especially to the improvement of the type and standard themselves in their turn to extend the bounds al of English secondary education that attention must knowledge. be at once seriously directed if full advantage is to Lord Strathcona in his address at the graduatit he made of English universities and technical colleges. ceremony also wisely insisted upon the nation. We have arrived at the stage when the pressing need character of the Scottish universities, and brought to is neither suitable buildings nor qualified teachers- | high relief a feature which should distinguishi