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applied to the surface of whatever it rests upon, contents of the crop and defæcating at frequent excrement or food-stuff, as opportunity offers. intervals, suggest it as an excellent inoculating

The alimentary canal comprises a gullet, agent for any bacteria it may pick up in the stomach, crop, intestine, and rectum (see Fig. 2). satisfaction of its catholic tastes. That it does, The gullet is prolonged forwards to a minute indeed, operate in this way has been abundantly opening between the flaps of the proboscis, half- demonstrated. Flies which have wandered over way down which it is joined by the salivary duct cultures of organisms and afterwards been allowed (SD). At the entrance to the stomach (S) it is to walk upon gelatin plates leave a rich crop of bifurcated, and one limb of the bifurcation is ex- germs in their footprints, which can be demontended backwards to the bilobed crop (C). By a strated by subsequent incubation. valvular apparatus at the entrance to the stomach, Flies fed in the laboratory upon material conthe insect can direct the liquid driven by the pump taining easily identifiable pathogenic microbes in its trunk into either the stomach or crop. The have been shown to harbour them in their crops proboscis is a highly elastic muscular organ with for days, and to deposit them in their fæces and universal movement. At the end are two flaps the regurgitations from their crops. Internal car

riage is probably more important than soiling of the exterior of the insect, as many pathogenic bacteria soon die from desiccation on the appendages of the insect.

In addition to these laboratory experiments,

there are numerous recorded instances in which FIG. 1.-Leg of a house-fly.

the pathogenic organisms of cholera, typhoid,

phthisis, anthrax, and plague have been recovered or labella (only one of which is shown), which it from the interior or dejections of flies which have can open out like the leaves of a book, and apply been captured in the immediate neighbourhood of the medial surfaces to the material it feeds upon. cases of the disease, or, in the last two cases, of From the middle line or hinge, minute chitinous

carcases of animals dead of the disease. channels pass outwards to the margin. At the Although, however, flies may be discovered with base of the trunk a number of muscle fibres are the infection of a number of diseases in or upon attached to the gullet by the peristaltic contraction them, and by their habits may not unlikely serve of which fluid is pumped up from the mouth and as agents in transferring infection, it by no means propelled into the stomach or crop. The struc- follows that they are the determining factor of tural arrangement of the channelled flaps of the epidemicity in the case of cholera, typhoid, dysentrunk acts as a filter, through which solid objects tery, etc. In the case of fulminating epidemics larger than 1/400oth in. seldom pass. When

of typhoid and cholera associated with an infected feeding on a liquid, the fly applies the labella to the

water supply, this is obviously not so. surface, and sucks the liquid through the

It is in temporary encampments of troops or pilgrims, when the disposal of excreta must necessarily be of a primitive character, that the conditions obtain which are most favourable to the breeding of flies and the distribution of infection by them, if cholera or typhoid appear. Even in these circumstances it is difficult to assess the relative importance of fly carriage and other means of spread, but the conclusion that fly transmission is the principal means of spread of typhoid in military encampments and stations has been

arrived at by a number of competent observers, FIG. 2.- Alimentary system of a house-fly.

amongst them the commission to inquire into the

origin and spread of typhoid fever in the United “strainer” first of all into the crop. When this is States military camps during the Spanish war of full, a further quantity is admitted into the 1898, and by a number of medical officers constomach. In the case of solid material, such as cerned with the severe outbreaks of enteric which sugar, the insect must first dissolve the material. occurred during the Boer war. This is done by pouring saliva upon it, or by re- The sanitary arrangements of a military camp gurgitating some of the contents of the crop. are not exactly those of the Ritz Hotel, and the

A well-fed fly deposits fæces abundantly, and prevalence of flies in late summer can scarcely be also the contents of its crop upon sugar and other appreciated by those who have not had camp exsolid objects.

perience. The conditions are most favourable for It is clear, therefore, that there are a priori transmission of disease by flies, and the circumreasons for suspecting the fly of carrying bacterial stantial evidence against them is so strong as to infection. Born in a dunghill, it spends its days have left no doubt in the minds of the American fitting between the sugar basin, milk pan, and Commission that these insects play a large part any fæcal matter available. Its hairy, probably in disseminating infection, for on page 28 of their sticky, feet and the habit of regurgitating the general statement and conclusions we read :

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"Flies undoubtedly served as carriers of infec- ing dejecta in the case of an outbreak of cholera tion."

amongst a limited population in the Puri jail. An estimate of the fly population and its relation These were attended with immediate good results. to admissions for enteric fever was made by There are the

general reasons for Ainsworth in Poona, where enteric has a very assuming that fly transmission plays an important definite season. A definite number of fly traps part in epidemics of summer diarrhæa of infants was set, and the daily catch taken as a measure as in the case of typhoid and cholera. Anyone of the fly population. The observations showed familiar with the domestic ménage of the average that the abundance of flies increased earlier than working man a hot summer day, with the the admissions for enteric, and, speaking gener- baby sick with diarrhæa, and other small children ally, the rise in fly population ante-dated the rise to care for, must realise that the opportunities in enteric cases by about one month.

afforded for flies to transport the infective agent Taking into account the incubation period for from the dejecta of one child to the food supply the disease, this fact is in agreement with the of another are more than adequate. view of a causal relation between cases and flies Epidemic diarrhea of children does not occur in Poona.

except during that season of the year when flies In considering the possible influence of Aies in are abundant and active, and, as will be seen the spread of typhoid in a well-sewered city, it from the accompanying chart, the relation bemust be remembered that the opportunities for tween fly population and diarrhæa cases is so them to pick up the infection are vastly fewer than under the conditions of a military encampment, or even in rural surroundings. In large cities with modern sewerage, dejecta and urine from patients may be left available to flies, but the bulk goes promptly into the main drain, and similar observations to those above-mentioned have shown no close relationship, in point

of time, between cases of typhoid and prevalence of flies in London, Washington, or Manchester.

As with typhoid, the against flies as agents in the distribution of the infection of cholera is circumstantial, as other means of spread cannot be excluded. Take, for instance, the case of accumulation of 300,000 pilgrims in Puri, India, in July, 1912, which was studied 13 June 20 27 July 11 23 Aug 8 15 22

1926 Det. 8 '10 V by Greig. The sanitary accommodation of the town was inade- Fig. 3. —Dr. Hamer's observations on relation in point of time between prevalence of Aies and diarrhæa quate for such an accession to

mortality in London, 1908. (141 fly-collecting centres.) The deaths from diarrhea have been ante

dated 10 cays the population. Some of the pilgrims imported the infection of cholera, and striking as to suggest something more than a an outbreak occurred. Flies in Puri “amounted

accidental dependence upon

the almost to plague,” and a bacteriological phenomena. examination of the legs and the contents of the The chart is constructed from Dr. Hamer's alimentary tracts of flies caught in the neighbour- observations on the numbers of flies caught daily hood of cholera cases demonstrated the presence in the same number of traps in 141 localities in of cholera vibrios.

London during 1908. An important point brought Knowing the habits of flies, it is impossible to out by these observations the dependence of forgo the conclusion, arrived at by Greig, that both the number of flies and the epidemic upon some amount of distribution of the infection of the cumulative effect of previous warm weather cholera was due to their activity. But to what a

-as, for instance, is indicated by the earth temextent they were contributing could only be perature four feet below the surface, a fact to ascertained by the result of measures directed which attention was directed by Ballard in 1889. either to the diminution of their numbers, or to Similar observations in Manchester, by Dr. Niven, depriving them of access to infecticus material.

in 1904 to 1906, showed the same relationship. Greig could not supervise the private latrines The reason why the number of flies should be of the native inhabitants, but was able to carry dependent upon this factor is obviously that out practical measures to prevent flies from visit- the generation time (cycle from egg to egg) is

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of the existence of the Babylonian legends of Creation and the Deluge; to say nothing of the inany relics of the arts and sciences of Babylon which the library of Assurbanipal preserved

for us.

dependent on temperature, and requires three weeks or upwards in our climate. Months of warm weather are therefore required to produce any multitude of flies from the few surviving in the winter. Why the epidemic should exhibit this dependence is not explained, unless on the assumption that the fly population determines the number of cases of diarrhea.

Without losing sight of the various other ways in which the specific infective agents of cholera, typhoid, epidemic diarrhæa, and dysenteries may be and are transported from the excreta of one individual to the mouths of others, the prima facie case against the house-fly is complete.

Further, in the case of infantile diarrhea, the fly-carriage hypothesis offers a satisfactory interpretation of the extraordinary dependence of the epidemic upon the accumulated effect of temperature, and affords a ready explanation of the spread of the infection of cholera, typhoid, and diarrhea to neighbouring persons who have no contact with the patient, in those cases in which contamination of a water or food supply may be excluded.

The direct proof of the extent of the danger due to flies is lacking, but the hypothesis has pragmatic value. It not only interprets facts otherwise awkwardly explained, but measures based upon it have been attended with beneficial results; in other words, it works.

The pathos of the position of the German explorers was that the site had been looted so often previously to their systematic investigations that scarcely anything of first-rate importance was left for the latest adventurers. The temples and palaces of Nebuchadrezzar's capital were probably swept bare of most of their portable treasures at a comparatively early period; and the ravages of people in search of building material, and the petty pilferings of Arabs and other stray visitors, had doubtless robbed the ruins of much that would have been priceless in the eyes of modern explorers. Even the beautiful enamelled bricks,

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From "The Excavations

THE RESURRECTION OF BABYLON.1 THOUGH scarcely, a book to attract the general

' reader, Dr. Koldewey's account of the German excavations on the mounds which have for ages entombed the remains of Babylon the Great, is a work of considerable importance for all who are interested in the archæology of the Old Testament. This, as perhaps is not generally known in England, is still a growing science; and the worst thing that can be said of the German Expedition to Babylonia is that, after so many years of patient and persistent spadework on one of the most promising sites in the world, it has not yet succeeded in unearthing anything of higher historical or religious value than is recorded in he Fig. 1.- Eramelled wall length of the Ishtar Gate. volume before us. Nothing extraordinary has

at Babylon." hitherto been found; no great literary monument, with their strange mythological figures, are not no document of supreme religious moment, no

altogether a novelty. Older specimens of the thing that lends decisive help towards the settle

same kind of mural decoration were long ago ment of any one of the unsolved problems of

reproduced by Perrot and Chipiez from Sargon's history or chronology. How much more fortunate

palace at Khorsabad (“History of Art in Chaldea in this respect were the pioneering labours of

and Assyria," II., plate xv.; see also plates xiiiLayard and George Smith and Botta at Nineveh,

xiv. Eng. Trans., London, 1884).

But it is of Rassam at Sippara, of De Sarzec at Tellô, of

highly satisfactory to find such splendid examples De Morgan and Scheil at Susa!

as those of the Ishtar Gate still existing, in situ, It is well for us that the Assyrian kings were

and in such an excellent state of preservation so deeply interested in the literary monuments of

(Fig. 1). Babylon. Had we depended for our knowledge

Whether anything of supreme value awaits disof these on the remains of the Great City itself,

interment at lower levels remains to be seen. we should (until the recent American discoveries

Slabs of diorite or other hard stone, like the at Nippur) have been left without any indication

famous stela of Hammurabi, or the similarly I “The Excavations at Babylon." By R. Koldewey. Translated by written inscription of Nebuchadrezzar, which is Agnes S. Johns. Pp. xix +335. (London: Macmillan and Co., Ltd., 1914.) Price 21s. net

(or was) one of the treasures of the library of the East India House, might well have survived an either he or his translator has misunderstood age-long immersion in Euphratean mud. In any Winckler (KB., iii., 2, p. 23), who explains IV case, disappointing as, in such respects, results M amat gagari, 4000 cubits of ground," as have hitherto proved to be, we entirely agree with referring to the length of the new wall, not to Dr. Koldewey that it is most desirable that the the distance from Imgur-Bel, and renders itāti work of excavating this historic site, begun so Bâbili nisis dahê, “an den Seiten von Babylon, many years ago, should be carried to completion. in der Ferne, sodass sie nicht herankam,' Meanwhile, the special student will not fail to find where “sie” also refers to the new wall. many good things in this storehouse of facts and We must also be excused if we demur to the comments. It is now certain that ancient accounts transcription “Sirrush ” and the explanation “a greatly exaggerated the extent of ground actually walking serpent” (p. 46). The çirrush, or rather, covered by the city, the influence of which dom- mush-rush, was one of the aqueous monsters inated the civilised world from the age of Ham- created by Tiâmat, to help her in warring down murabi, the founder of its imperial greatness, to the gods of light. It is something to learn what that of Nebuchadrezzar, who, if he did not find a MUSI-RUSH was like; and Dr. Koldewey has it of brick and leave it of marble, undoubtedly enabled us to identify it with a form already

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restored and enlarged its walls and temples and familiar to us from other Babylonian monuments. palaces on so grand a scale that the glories of It was, in fact, not so much a serpent (though Babylon the Great became a standing wonder of the Sumerian Mush includes that meaning) as a antiquity. The walls, however, have been found composite form with serpent head, scales, and to range from upwards of fifty to more than sixty tail, and four claw-footed legs--a sort of "laidly feet in thickness, and the mounds which concealed worm" or "fearsome dragon," and remarkably them rose to about four times the height of the like a dinosaurus. The name may denote fierce ordinary Tels of buried Oriental cities : circum- (or glittering) dragon (Fig. 2). stances which sufficiently indicate the arduous Dr. Koldewey first visited Babylon in June, nature of the task of excavation.

1887, about the time when the present reviewer Dr. Koldewey's translations are, for the most was working upon the text of the East India part, good and accurate; but in EIH. VI. (not House inscription of Nebuchadrezzar (see Pro"7") 22-55, the passage in which Nebuchadrezzar ceedings of the Society of Biblical Archæology, or his court historian describes the building of December, 1887). What a godsend would the the new eastern wall and the making of the moat, present volume have been in those days, clearing up as it does by its thorough investigation of Thus, sections are devoted to "thermit,” the eleclocal conditions and the actual remains of the trolytic cleaning of tarnished silver by contact ancient buildings so many of the earlier trans- with aluminium in a solution of soda and salt, lators' almost hopeless perplexities ! One after the preparation of colloidal solutions of platinum another, the Procession Street of Merodach, the and gold, etc. The following description of a Sacred Way along which marched the annual method of soldering aluminium may prove useful solemnity of Babylon's tutelary god; E-MAGH, the (p. 47) :-temple of NIN-MAGH, “The Exalted Lady,” several

Aluminium, inscribed cylinders from which may be seen in

I part; zinc, 4 parts. After the

aluminium has been melted add the zinc, then a small the British Museum collection; the Gate of Nanâ

quantity of fat. The mixture should be well stirred, Ishtar, with its superb enamelled figures; the after which it may be poured into stick moulds. palace of Nabopolassar (Nabû-apla-uçur), which To apply, scrape the article bright at place to be Nebuchadrezzar restored with great splendour;

soldered. Use a little Venetian turpentine as a solderthe location of E-SAG-ILA, the temple of Merodach,

ing fluid, Athin shaving of the solder may then be and chief sanctuary of Babylon; the world-famed

placed around the jcint and melted with a blow torch. walls, and various connected structures, were It is impossible to mention the very large determined and in part exposed to view.

number of technical and scientific principles which All this, though perhaps not exactly the kind are described and illustrated; it must suffice to of matter to stimulate the enthusiasm of one who say that these range from the production of reads merely to while away an idle hour, con- Pharaoh's serpents, through electric motors and stitutes a highly important contribution towards an exact topography of Babylon, and to the right understanding of the inscriptions of the Neo-Babylonian period; while it enables classical students to bring to the test of. ascertained facts the descriptions of Babylon which we find in Herodotus and subsequent Greek and Latin authors, extracts from whose pages are given in Koldewey's convenient appendix. It is to be hoped that current events in the East may prove no bar to the further prosecution of Dr. Koldewey's meritorious and, indeed, necessary enterpriseeven if it happen by the fortune of war that the whole or part of the treasures recovered by his continued labours should find their way to London instead of Berlin.

Fig. 1.-Engine ruom of submarine looking forward. From " Discoveries and Inventions of the It should be added that the

Twentieth Century." author has been fortunate in his translator, the English of the book being generally

dynamos, to wireless telegraphy and X-rays. The accurate and readable—which is not always the

last nine chapters are devoted to an analysis of case with translations from German originals.

the principles used in research and invention. The C. J. BALL. book is well got up, and forms interesting and

instructive reading.

(2) Although the twentieth century is still SCIENCE AND INVENTION.1

young, Mr. Cressy has found nearly four hundred

pages to be none too many in which to describe (1) MR.

the progress of inventions made therein. The redescriptions of a number of scientific

markable improvements which have been made in experiments, illustrated by small but clear dia

the details of most industries are clearly brought grams. Some of these experiments will be

before the reader. The modern applications of familiar to all those who have taken an experi

water power, as exhibited in the water turbine mental course in chemistry and physics, but fresh

and the Pelton wheel; the developments of the ness is given by including simple instances of

steam turbine; the Humphrey pump; improvetechnical applications of scientific principles.

ments in gas, petrol, and oil engines, including 1 (1) " Experiments. A Volume for All who are Interested in Progress." the Diesel marine engine, and the “Gnome By P. E. Edeln an. Pp. 256. (Minneapolis, U.S.A. : Philip E. Edelman, 1914.) Price 1.50 dollars.

engine for aeroplanes; these form a few of the (2) "Discoveries and Inventions of the Twentieth Century.". By E. developments described in the first few chapters. Gressy. Pp. xvi + 398. (London: G. Routledge and Sons, Ltd., 1914.) Price 7s. 6d. net.

Electric lighting is next discussed, and some in

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