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makes no pretence of doing, as, of course, its dis- | so rapidly that it is quite within the bounds of tinguished authors would at once admit. But mass, | possibility that the liquid-fuel question may in the as we have seen, is not conventionally defined with near future be placed above the control of price and reference to gravity, but .by means of inertia, or geographical position. momentum at unit velocity. As a moving electric In dealing with the economic aspect of liquid fuel charge can be shown to possess this momentum, it is it is pointed out that although the a strictly correct use of words to say that the electron advantages accruing from its
early theory explains the property of mass.
recognised, the prohibitive price prevented any great Dr. Hampson argues, in the second place, that advance in its use, but that with the increase in outelectricity is a form of energy, and that it cannot there- put its utilisation now comes within the range of fore be identified with matter.
practical possibility, and that the advantages in “ When an electrical machine is used to charge winning, transporting, and storing and using the a Leyden jar . : . there is no change in the quantity oil, especially for marine purposes, are so great that of materiál substance with which operations were the supply of the liquid fuel is now the only factor started; it is the mechanical energy driving the checking its universal introduction. machinery that has been converted into electricity In considering the absolute economy as a fuel, the (p. 87).
author very properly leaves out the extravagant The misconception here lies in confusing the separa-claims made by some of the early experimentalists, tion of positive and negative electricity with the and only gives the best authenticated values, which creation of either. Take the case of a Leyden jar. vary from 12.5 to .16 lb. of water evaporated per lb. The coatings of the jar, according to modern views, of liquid fuel. Variations in the use of oil as a fuel initially both contain a number of chemical atoms, all are of course largely dependent upon the method by with their normal complement of constituent electrons. which the oil is burnt, and too little stress is put upon The operation of charging consists in the removal the importance of the space factor, which is a most of some of these electrons from the outer coating, essential one, as, given plenty of combustion space in say, and their transference to the inner one. This the boiler, the smokeless burning of liquid fuel is a leaves the outer coat with a defect of electrons, and perfectly simple problem, which, however, increases therefore positively charged, while the inner one enormously in difficulty as the available space becomes acquires an excess of them, and consequently becomes more and more cramped. negatively charged. The transference involves the The chapter on the chemical composition of fuel expenditure of energy on the electrons, but no alter- oils gives an excellent summary of analytical results, ation in their number, and therefore no change in and this ends with a table showing the composition, the amount of matter concerned.
calorific value and evaporative power of different We are sorry to have had to dwell principally on descriptions of British coal. This, however, is liable the parts of the book with which we disagree, as to lead to misconception, as the value expressed in the are but a small portion of the ole, and do lb. of water evaporated per lb. of fuel is calculated, not detract from the usefulness of the rest.
and not that obtained in practice, so that the reader R. J. S. who finds that by this. table i lb. of Welsh coal will
evaporate 14.98 lb. of water will be a little puzzled
to see where the large economy comes in, when i lb. OIL FUEL.
of oil only evaporates from 12.5 to 16 lb. of water. Oil Fuel: Its Supply, Composition and Application. As a matter of fact, all recent work points to the
By S. H. North. Pp. viii + 152. (London : Chas. relative evaporative results under the best conditions Griffin and Co., Ltd., 1905.) Price 5s. net.
being 9 lb. of water per lb. of coal, or 15 lb. of water MR. R. SYDNEY H. NORTH has utilised the store
per lb. of oil, whilst the theoretical results give of data collected whilst he was editor of the 14.98 lb. of water for coal, and 20 to 21 lb. for oil. Petroleum Review to supply a most valuable addition
The section dealing with the conditions of comto Griffin's scientific text-books in his work on “ Oil bustion in oil furnaces is a useful reproduction of the Fuel" and to give his readers a concise and valuable views expressed by Messrs. Ord, Paul, and Lewes, record of the developments in the use of liquid fuel and the author does not venture on any generalisation for the generation of power.
of his own. In the first chapter of the book he deals with the Turning from consideration of the oil itself to the distribution and sources of supply of petroleum, and
methods of burning it, the author gives a very useful points out that the chief sources are
historical summary of the early experiments down to graphically situated as to place the United Kingdom the year 1883, when Mr. James Holden, whose name at a disadvantage in case of war, should the use of will always be inseparably connected with the subject liquid fuel be largely adopted in the Naval Service, of liquid fuel, introduced his method of consuming the a fact which accentuates the importance of develop
oil on the Great Eastern Railway. ing such fields as those of Canada and Burmah, and A chapter is then devoted to modern burners also of opening up new areas where possible in British and methods, and steam, air, and mechanical Possessions.
injectors are discussed. The author very properly In concluding this portion of the work, the author concludes that expresses his opinion that recent developments and " for the successful use of liquid extensions of oil-bearing areas are now progressing to be
that auxiliary apparatus
fuel it appear
and extraneous sources of heat must be avoided, and of reactions. Simple consecutive changes determine the furnaces made practically self-contained, if any, the character of many apparently complex reactions thing approaching perfection is to be attained. It
In connection with the determination of the number must be upon simplicity, ease of working, and freedom from complicated parts that the progress of liquid of molecules taking part in reactions in gaseous fuel must chiefly depend.
systems the author sounds a very necessary warning “ The direct pulverisation of the oil is now coming note. The rate of decomposition of phosphine or to be recognised as the proper method ; it is the most arsine is a frequent text-book illustration of oor of efficient and the most economical."
the methods employed, and the experimental data fit The next two chapters are devoted to discussing the in with the assumption that the reaction is unimole. use of oil fuel for marine and naval purposes, but the cular and non-reversible. But there is another side division into two chapters is hardly needed, as the to this and similar problems. It is not improbable naval side of the question is scarcely touched upon, the that the reaction takes place on the surface of the bulk of the matter in that chapter being taken up walls of the containing vessel, and that its rate is with the trials of liquid fuel on the s.s. Mariposa, and conditioned solely by the rate of absorption of the gas the tests made on land by the American Liquid Fuel by this surface. The course of the reaction will in Navy Board.
this case also be that of a unimolecular change. The chapter on oil fuel in locomotives is an In the section on the measurement of chemical excellent summary of the work of Urquhart and affinity we meet old and familiar friends in the illusi Holden, whilst the use of oil fuel for metallurgical trations of the thermal and density methods of comand domestic purposes also receives some attention. paring the affinities of two acids. The very moderate
The whole work compares very favourably indeed accuracy attainable in these methods, which involve the with the far more pretentious treatise on the subject small difference between two experimental quantities which until now has been the only book of reference, and in which corrections have frequently to be intro and everyone interested in this important question will duced in consequence of secondary changes, in welcome Mr. North's excellent text-book,
scarcely ever sufficiently emphasised, and attention might have been directed to this point. I method
depending upon the measurement of property THE DYNAMICS OF CHEMICAL CHANGE. possessed by only one component of a system has Chemical Statics and Dynamics. By J. W. Mellor,
obvious advantages, even if such methods are
relativ D.Sc. (N.Z.), B.Sc. (Vict.). Pp. xiii + 538. (Lon- limited application. Whether Thomsen's don : Longmans, Green, and Co.) Price 75. 6d.
avidities and the relative ionic affinity coefficients are
always identical conceptions is left for the readtt to OR some years past a marked increase of atten
infer. tion on the part of English chemists towards the rapidly developing physical chemistry has been
Chapter x., dealing with catalysis and the theon observable. Until recently, however, the available
of chemical change, is most attractive reading. Hery English literature on the subject was confined to
the processes of slow combustion or autoridation art German translations, a state of things which is now
discussed in the light of the theories of Brodie being in a large measure remedied.
Schönbein, Clausius, 't Hoff, Traube, Bach, The present work forms one of the series of text
Engler and Wild, and the interesting phenomen. books of physical chemistry edited by Sir William
included under induced or sympathetic reactions an Ramsay. According to the table of contents, four
treated. In the chapter on explosions the account of chapters are devoted to the consideration of homo- older work is supplemented by many new and interest geneous reactions, and in succeeding sections the
ing facts. initial periods in chemical change, heterogeneous
In the reviewer's opinion Dr. Mellor's work is to be reactions, equilibrium and dissociation, electrolytic
warmly recommended. The fact that it contains thris
thousand or dissociation, catalysis and the theory of chemical
so references to original papers is in
itself evidence of its utility to the teacher, to the change, fermentation, the influence of temperature and pressure in chemical reactions, and finally ex
advanced student, and to the physical chemist (s)plosions, are dealt with.
gaged in research.
H. M. DAWSOX. Since the appearance of van 't Hoff's “ Etudes de Dynamique Chimique a vast amount of work has been done in connection with the problems involved
RECENT EARTHQUAKES. here, and the necessity for a summary of newly dis
A Study of Recent Earthquakes. By Charles Davison, covered facts, a criticism of recent theories, and an
Sc.D., F.G.S. Pp. xii + 355; So illustrations unbiased statement of our present position in regard (London: Walter Scott Publishing Co., Lid. to the dynamics of chemical change and allied
Price 6s. problems must have been felt by many. Dr. Mellor's
N this copiously illustrated volume Dr. Charles work will, therefore, receive an undoubted welcome.
Davison, whose seismological investigation The accumulated evidence on the nature of chemical especially those relating to British earthquakes, ar change resulting from kinetic studies leads the author well known, gives a popular account of the trauka to favour the view that the association", which have been arrived at by modern seismology “ intermediate compound” theories describe in the The method in which he treats his subject is one that most rational manner the mechanism of the majority appeals to the general reader. Rather than grouping
seismic phenomena, as we should expect to find them of ordinary intelligence than for the specialist, here in a text-book, the author has given a concise history and there we come upon information of an uncommon of eight disturbances, each of which has a special kind. For example, it is pointed out that the areas interest. The Neapolitan earthquake is of interest over which earthquake sounds are heard is variable in from an historical point of view, the Ischian earth- different countries. One reason for this is that the quakes illustrate the relationship between volcanic and limits of audibility vary with different races. From seismic activities, a Japanese earthquake is described illustrations given it would appear that for certain on account of the fault line which was produced at the sounds the Anglo-Saxon ear is more acute than the time of its occurrence and the numerous after shocks Neapolitan, and very much more than that of the by which it was followed, whilst a British earthquake Japanese. This relationship between the physiological illustrates the growth of a fault. From the work of structure of the human ear and earthquake music is, Robert Mallet upon the first of these earthquakes, to say the least, extremely interesting, but while diswhich in 1857 devastated a district to the south-east cussing the same the fact must not be overlooked that of Naples, and when upwards of 9000 people lost their in the same country districts may be found where lives, the scientific world learned that out of ruins much seismic sounds are frequent, whilst there are other might be learned respecting the direction and intensity districts where Pluto shakes the ground but mutterings of the movements which had caused them. Although are never heard. his methods of investigation, as, for example, those
Dr. Davison's book is well worth reading, whilst the relating to the determination of the depths of seismic manner in which its contents have been arranged foci, may have been modified by new observations, should obtain for it a circulation amongst those who Mallet directed attention to new problems for the solu
seek for general information. tion of which he employed scientific methods.
The Andalusian earthquake in 1884, we are told, is chiefly remarkable from the fact that it was recorded
OUR BOOK SHELF. at very distant stations, as, for example, by magneto
A German-English Dictionary of Terms used in graphs near Paris, at which city the movements of the Medicine and the Allied Sciences. By Hugo Lang ground could not be felt. For this disturbance the and B. Abrahams. Pp. vi + 598. (London: J. depth of its origin is determined by means of angles of
and A. Churchill, 1905.) Price 155. net. emergence calculated from the directions of fractures There is undoubtedly a vacant place which would be in masonry walls. That the direction of these fractures filled by a well-compiled work bearing the above title. might be due to the varying steepness of the earth
The book now under review has a certain claim on our
regard in this connection, and in some respects is a waves which produced the shattering is not
useful work. It purports to be, in the first place, a sidered
medical dictionary, and, so far as we can judge, fulfils The peculiarity of the Charleston earthquake is that this promise in a satisfactory manner. With a few it occurred in d region where such disturbances are minor blemishes there is a complete vocabulary of almost unknown, that it had two foci about thirteen
medical terms, and as a rule these are very fairly miles apart, and that it illustrated the behaviour of rendered by their English equivalents. But in the different races when confronted by a terrible disaster.
allied sciences, which are also supposed to be included.
there are curious lacunæ. Chemistry is pretty well With the negroes there was wild fear, panic, and a represented-for example, we found most of the * selfish rush for safety.” With Europeans in similar technical terms in Biedermann's Chemiker Kalencircumstances similar conditions prevail, but we are dar " duly set down--but the pathological vocabulary told that with Japanese there is calmness. Our own
leaves much to be desired, and apparently physiology is
not considered an allied science at all—at any rate, idea is that Japanese like to save their necks as well as
very seldom to be other people. They will bolt at the time of an earth- with. quake, to return, not with hysterical and shattered The authors have generally avoided the pitfalls set nerves, but chattering and laughing as if earthquakes for the unwary in works of this kind, and there are were very fine jokes.
few actual mistakes; occasionally it is difficult to ascer1 subject attractive to the general reader which is
tain the real meaning of a word without extraneous referred to in several chapters is an account of signs self is not correctly translated by “ typhus"; it in
assistance. For example, the word “ typhus” by it. which have given warning of a coming earthquake. variably means “ enteric” (typhoid), and the English C'nderground sounds have been heard, springs have typhus fever is “ fleck-typhus,” the latter being, howvaried in their flow, horses, birds, dogs, and even
ever, correctly entered in its place. The medical meanhuman beings have been restless for some time before ing of “ Belastung" is given; the completely different
signification when the word is applied to muscle is great earthquakes. In his reference to the Riviera
omitted. But the cardinal fault of the dictionary is the earthquake in 1887, Mr. Davison remarks that as pre
treatment of compound words. These are separately monitions were noted at 130 different places within the set forth at length instead of being collected under central area, “there can be little doubt that they were their first components, and this increases the bulk and caused by microseismic movements for the most part
cost of the work (already too great) without conferring insensible to man." In these days of psychical research
any real ease of reference. The courteous way in which we think that the author has lost an opportunity for
the authors in the preface invite suggestions disarms
too caustic comments, and we merely hint gently that romantic speculation.
in the next edition the space that could be saved by the Although the book is intended more for the person course indicated could be profitably employed by the
insertion of a few additional pathological and physio- of the mineral, but during the past year additional crystals logical terms, and that it would be unwise to trans- have been acquired for the British Museum, and from late these in the fashion adopted at present in such
these about eighty milligrams of fairly pure material have words as “luftweg."
been obtained for chemical analysis. Thallium is present (up to nearly 20 per cent.), together with lead, silver, and
copper, in combination with arsenic and sulphur. A full Règles internationales de la Nomenclature
description of the mineral will appear shortly in the logique. Pp. 63. (Paris: F. F. R. de Rudeval, Mineralogical Magazine.
G. T. PRIOR. 1905.) It has frequently been remarked that it is not of
The Legendary Suicide of the Scorpion. much use making laws and regulations unless you have the power to enforce their observation; and this I have recently come across the following passage in the trite saying applies, in our opinion, very forcibly to
Rev. John Campbell's " Travels in South Africa " (London, this code of regulations for zoological literature, drawn
1815), p. 38 :-“ Having caught a scorpion near our tent.
we tried whether naturalists were accurate in relating that up by an international committee the deliberations of
if that animal be surrounded with fire, and sees he cannot which have extended over some years. The code,
escape, he will sting himself to death. However, it died which is published in three languages, is admirably
as quietly as any other animal, only darting its sting frum drawn up, and for the most part free from ambiguity; it, as it to oppose any ordinary assailant.” The experibut the question is, will naturalists agree to abide by
Zwellendam, Cape Colony, on it? In our opinion, a large number will refuse to February 20, 1813.
EDWARD B. POULIOK. accept it, since a rigid and slavish adherence to the law Oxford, March 31. of priority is enjoined, and to many this is anathema. The rule that when a genus-name is changed this entails the change of the family title will be generally
Propagation of Earthquake Waves. regarded as satisfactory. As regards emendation in
A FEW days ago I read Major C. E. Dutton's book on names, this is held to be justifiable only when an Earthquakes in the Light of the New Seismology.' error in transcription, a lapsus calami, or a misprint While acknowledging the high merits of this book, I iake is apparent; but in the interpretation of this diffi- the liberty of pointing out some statements which secm culties may arise, as in the well-known case of misleading. Neurogymnurus, which is believed to be an error I refer to chapter xiji., where the author, quoting the for Necrogymnurus. Differences of opinion, again, results of the experimental investigations of Mr. Nagaoka, are likely to arise with regard to the rejection of gives the speeds V, and V, of the normal and transvers
Now a glance at the table on pp. 230 and 251 names on account of unsuitableness or similarity to
shows that for many rocks the two moduluses E, and E, others already in use. The retention of such names
perpendicular and parallel to the bedding planes are far as Polyodon and Apus when applied to animals which
from being equal; on the contrary, the quotient E, E, do not properly come under such designation will,
varies so much as from 1.43.! 2.49 for rhyolite cuff to no doubt, be generally accepted; but what is to be
32.1/ 17.5 for rhyolite. Hence the physical properties of said when, for instance, an essentially African species the rocks in question are different in different directions is named asiaticus? Such
as Polyodus, and the speeds of propagation of waves are also different Polyodon, Polyodonta, Polyodontus, &c., are held not in different directions, so that the speeds V, and V, of to come under the category of synonyms, although the table being the same for all directions have no real the converse rule is followed in many systematic works meaning for many rocks. and catalogues, such as Dr. Trouessart's “ Catalogus Again, in chapter xiii. and in other chapters of the Mammalium.”
book, the author refers to normal and transverse waves As a “ pious
in rocks. It would be better, perhaps, to speak of dilaexpression of opinion on the part of
tational and torsional waves; but leaving the question of the International Committee the “ Règles
terminology out of consideration, I observe that it is only doubt, valuable; but they would have been much more
for perfectly elastic homogeneous and isotropic bodies that so had a plebiscite of zoologists and palæontologists
the separation of the dilatational (normal) from the agreed to accept and abide by the ruling of the com
torsional (transverse) wave takes place with certainiv mittee.
We have no right to extend this property to æolotropic bodies. When the body is æolotropic the deformation of an element on the passage of a wave need not be of a purels
dilatational (normal) or of a purely torsional (transverse) LETTERS TO THE EDITOR.
character; it is rather of a mixed nature. [The Editor does not hold himself responsible for opinions
I will not say that æolotropic bodies able to propagate
purely dilatational and purely torsional waves cannot exist. expressed by his correspondents. Neither can he undertake
but I observe that such bodies are to be considered rather to return, or to correspond with the writers of, rejected as possible exceptions, inasmuch as certain special conmanuscripts intended for this or any other part of NATURE. ditions must be fulfilled in order that the generation of No notice is taken of anonymous communications. ] purely dilatational and purely torsional waves should be
rendered possible. So, for example, the elastic potential ai A New Thallium Mineral.
a perfectly elastic homogeneous uniaxial body implies five
independent constants. When we introduce the condition THE element thallium, discovered by Sir W. Crookes that purely dilatational waves may be propagated apart in 1861, has up to the present been known as an essential from torsional ones, we find that two definite relations constituent of only two minerals, viz. crookesite, a selenide between the constants must be satisfied so that the number of copper and thallium, and lorandite, a sulpharsenite of of independent constants is reduced to three. But or the latter element. To these minerals a third must now have no reason to maintain a priori that the conditions in be added in hutchinsonite, a new sulpharsenite from the question must be always satisfied. Binnenthal, which also contains thallium as an important Of course it is to be understood that a perfectly elastic constituent. The crystallographic characters of hutchin- homogeneous uniaxial body cannot be considered as an sonite were described about a year ago by Mr. R. H.
model ” of stratified rocks; it is only very similar Solly, who, of late years, has been particularly successful to them ; but it is more than highly improbable that the in discovering new mineral species in the Binnenthal. At effect of internal friction would neutralise the effect of the time of its discovery very little in the way of chemical æolotropism.
M. P. RUDZKI investigation was possible owing to the extreme scarcity K. K. Sternwarte, Krakau (Austria), March 24.
of the year.
NOTES ON STONEHENGE.'
the sight line has been changed in the Egyptian
manner. The first is the three circles of the Hurlers, V.-ON THE STAR OBSERVATIONS MADE IN BRITISH near Liskeard, a plan of which is given in “ PreStone CIRCLES.”
historic Stone Monuments of the British Isles : CornHE work I have tried to do so far on our British
wall," by H. C. Lukis, published by the Society of stone circles has dealt with the observations of
Antiquaries, who were so good as to furnish me with the sun made in connection with them, and the
a copy, and also some unfolded plans on which sight attempt to determine a date has been based upon the
lines could be accurately drawn and their azimuths slow change in the obliquity of the ecliptic which is
determined. I am anxious to express my obligations continually taking place.
to the council and officers of the society for the help
thus afforded me. In continuation of my work in Egypt in 1891, and Mr. Penrose's in Greece in 1892, I have recently
The second is at Stanton Drew, in Somerset, conendeavoured to see whether there are any traces in sisting of three circles, two avenues, and at least one Britain of the star observations which I found con
outstanding stone. These were most carefully surnected with the worship of the sun at certain times veyed by Mr. C. E. Dymond some years ago, and We both discovered that stars, far out of
he was good enough to send me copies of his plans the sun's course, especially in Egypt, were observed in
and levelling sections. the dawn as heralds of sunrise-“ warning-stars "-SO
How can such plans help us? The easiest way for that the priests might have time to prepare the sunrise
the astronomer-priests to conduct such observations in sacrifice. To do this properly the star should rise indicating the direction of the place on the horizon
a stone circle would be to erect a stone or barrow
horizon I stated (“ Dawn of Astronomy," p. 319) that Spica
at which the star would rise. If the dawn the star was the star the heliacal rising of which heralded
was to herald occurred in the summer, the stone or the sun on May-day 3200 B.C. in the temple of Min
barrow itself might be visible if not too far away, at Thebes. Sirius was associated with the summer
but there was a reason why the stone or barrow solstice at about the same time. The equinoxes were
should not be too close; in a solemn ceremonial the provided for in the same way in Lower Egypt, but
less seen of the machinery the better. they do not concern us now.
Doubtless such outstanding stones and barrows Mr. Penrose found this May-day worship continued
would be rendered obvious by a light placed on or Athens on foundations built in 1495 B.C. and
near them. Cups which could hold oil or grease are 2020. B.C., on which the Hecatompedon and older
known in connection with such stones, and a light Erechtheum respectively were subsequently built, the
thus fed would suffice in the open if there were no warning star being now no longer Spica, but the
wind; but in windy weather a cromlech or cluster of the Pleiades.
similar shelter must have been provided for it. It is generally known that Stonehenge is associated Now if these standing stones or barrows were ever with the solstitial year, and I have recently suggested
erected and still remain, accurate plans-not the that it was originally connected with the May year;
slovenly plans with which Ferguson and too many but the probable date of its re-dedication, 1680 B.C.,
others have provided us, giving us either no indicawas determined by Mr. Penrose and myself by the
tion of the north or any other point, or else a rough change of obliquity.
compass bearing without taking the trouble to state Now if Stonehenge or any other British stone circle
the variation at the time and place—will help us in could be proved to have used observations of warning stars, the determination of the date when such
The work of Stockwell in America, Danckworth in observations were made would be enormously facili
Germany, and Dr. W. J. S. Lockyer in England has tated. Mr. Penrose and myself were content to think
provided us with tables of the changing declinations that our date might be within 200 years of the truth,
of stars throughout past time, or enough of it for our whereas if we could use the rapid movement of
purpose. stars in declination brought about by the precession
An accurate determination of either the azimuth of the equinoxes, instead of the slow change of the
(angular distance from the N. or S. points) or amplisun's declination brought about by the change of the
tude (angular distance from the E. or W. points) of value of the obliquity, a possible error of 200 years
the stone or barrow as seen from the centre of the stone would be reduced to one of 10 years.
circle will enable us to determine this declination. In spite of this enormous advantage, so far as I
This, of course, only gives us a first approximation. know no one has yet made any inquiry to connect
The angular height of the point on the horizon to star observations with any of the British circles.
which the alignment or sight-line is directed by the I have recently obtained clear evidence that some
stone or barrow from the centre of the circle must circles in different parts of Britain were related to
be most accurately determined, otherwise the declinthe May year, a vegetation year, which we know was
ations may be one or two degrees out. general over the whole of Europe in early times, and
To come back to the two cases to which I have which still determines the quarter-days in Scotland.
referred, the Hurlers and Stanton Drew. I will begin If the Egyptian and Greek practice were continued with a reference to the available descriptions of the here, we should expect to find some indications of
circles. the star observations utilised at the temple of Min and
The three circles of the Hurlers, some five miles at the Hecatompedon for the beginning or the other
to the north of Liskeard, are thus referred to by chief months of the May year.
Lukis in the valuable monograph which I have Following the clu given me in the case of the already mentioned. Egyptian temples, such as Luxor, by successive small
“ On the moor, about a mile to the south of the changes of the axis necessitated by the change in
singular pile of granite slabs, which rest upon and a star's place due to precession, I have looked out for overlap cach other, and is vulgarly called the this peculiarity in an examination of many maps and
Cheesewring, there are three large circles of granite plans of circles.
stones placed in a nearly straight line in a northI have already come across two examples in which north-east, and south-south-west direction, of which El Continued from p. 393:
the middle one is the largest, being 135 feet in * This article is generally based upon a note communicated to the Royal
diameter, the north no feet, and the south 105 feet. Society on March 15.
" The north Circle is 98 feet, and the south 82 feet