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to have become much more frequent of late years, and, ascertain how far such views were correct, I studied the in fact, it is doubtful whether in former times it ever Registrar-General's reports for the times of fogs; but, as occurred. The immediate cause of this new form of fog I found it difficult to interpret the figures, I have exis difficult to explain.

pressed them by the curves upon these somewhat lengthy London has always been the head quarters of town diagrams (Figs. 1, 2, and 3). I have selected times of fogs, but now all the large towns appear to be emulating fog, viz. the winters of 1879-80, 1889-90, and 1890-91, it in this respect, and this is what we must expect; an and have represented graphically the temperature, the increase of population means an increase of combustion amount of fog, and the death-rate for each day. of coal, and that implies a pouring into the atmosphere The results are, I think, worthy of careful study. The of more and more carbon, hydrocarbons, and sulphuric first thing we learn from these diagrams is that by far the acid. In dry and windy weather all these bodies may be greater number of fogs occur when there is a great fall of scattered so as not to produce appreciable effects ; but temperature ; and clearly this is closely followed after a few let the air be still, and even approach a state of aqueous days by a great increase in the death-rate ; but how much saturation-then, we have seen, every particle of dust and of this increase is to be attributed to the fog and how dirt becomes a centre for moisture to deposit on, and we much to the fall in temperature may be difficult to detershall have a fog imprisoning all impurities and offering mine ; but we have evidence that when fogs occur withthem to us for inhalation. To burn coal so that only out fall of temperature they do not appear to be followed

Explanation of Diagrams.- The amount of fog is represented by the small dark patches, the denser the fog the deeper the patch; thus the RegistrarGeneral reports that it is either haze, foggy, fog, thick fog, or dense fog. These different degrees of fog are represented by the vertical thickness : thus dense fog is 5 times as deep as haze, and so with the other designations.

The horizontal line represents the average temperature for each day for the previous 20 years, and also the average weekly death-rate from diseases of the respiratory organs for the previous 20 years.

The curved line rtp sents the divergence of temperature from the daily average, and the shaded part the divergence of the death-rate from the average.

Scale : inch represents 1 day, 1° F., and 10 deaths.

1879 – 1880
OCTI
NOV
DEC
JAN

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products of complete combustion shall escape is a by any remarkable increase of death-rate ; for, on problem of much difficulty, and is comparatively rarely December 15, 1889, there was a dense fog, and the done. Certainly the domestic fireplace does not do it, temperature was even above the average: under these but, on the contrary, is the principal cause of the dark conditions the death-rate remained far below the average. colour of our fogs. Many manufacturers, however, On December 13 and 14 in the same year, again, there liberally contribute produce the same effect.

is a dense fog, an average temperature, and only an I turn now from the constitution and production of fog to average death-rate; and the same thing happens on note some of the effects it produces. First, with regard to February 4 in 1890, when, notwithstanding a dense health, details on this point I leave to ihose who are fog, the death-rate remained remarkably low; and last more able to describe them than I am, but I have a few winter, on November 13 and 14, there was again a dense words to say with regard to the effect of London fogs on fog, a high temperature, and an average death-rate. the death-rate in general

. There are many people who With these four exceptions depression of temperature feel so strongly the unpleasantness of fog that it induces goes with fog. There is no case of depression of temperathem to magnify its results, and make extraordinary state- ture not followed by increase of death-rate. ments with regard to the mortality it produces. It has That many people suffer much, both physically and even by some been likened in deadliness to the Greatmentally, from ihe effects of fog, there can be no doubt ; Plague of London, and to other great epidemics. To but, as far as I can interpret these returns of the RegistrarGeneral, they do not confirm the popular impression that bare, and it is impossible ever again to recover them into fog is a deadly scourge; at the same time, it is beyond sightly specimens. (2) The toxic influence of the fog. doubt that an atmosphere charged with soot, dust, and This is most striking. It is illustrated in the most forcible empyreumatic products is an unwholesome atmosphere way by the inclosed memorandum. I attribute it in the to breathe ; but I think that the principal cause of the main to sulphurous acid, though I cannot help suspectgreat increase of death when fogs occur is attributable ing that some hydrocarbon may also have something to rather to the sudden fall of temperature which usually do with it. The toxic effect varies from one plant to accompanies fog, than to the fog itself.

another, some are scarcely injured, others are practically So many toxic effects are now traced to the action, killed.” He adds :-“I hope you will be able to arouse direct or indirect, of bacteria, that it is satisfactory to : some interest in this horrible plague. If the visitation of

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learn, from the experiments of Dr. Percy Frankland, that last year is annually repeated, it must in time make all fogs do not tend to concentrate and nurture them, for he refined horticulture impossible in the vicinity of London." found there were remarkably few bacteria in London air I append to this paper the very interesting and imduring a time of fog. The deleterious action of town portant report to which Prof. Dyer refers, from Mr. W. fogs on plants is more marked and more easy to inves- Watson, “On the Effect of Fog on Plants grown at Kew." tigate than its effect on animals. Nurserymen have This fog action on plants is so clearly marked, and so long known from experience that a town fog will pene- deadly, that it has, I am happy to say, led the Horticultrate even their heated greenhouses, and with certainty tural Society, aided by a grant from the Royal Society, to will kill many of their plants, specially their orchids, undertake a scientific investigation of the matter. Plants

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MARL 26-12-8 9-15/16-22/23-29 30-67-13 4-2021-27 28-02-solli - 019-24125- 311 - 78 - 14/15 - 2122-281 - 78-14

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FIG. 3.

tomatoes, and, in fact, most tender and soft-wooded are so much more easily dealt with than people, all the plants ; but on this point, I cannot do better than read circumstances of their attack by the fog and its immediate to you what the Director of Kew Gardens, Prof. Thisel- results so much more easily noted and traced, that the ton Dyer, says in a letter to me :-“With regard to investigation has already yielded important results, and plants under glass, the effect of fog is of two kinds—(1) By we shall, I hope, hear from Prof. Oliver-who is devoting, diminishing light. This checks transpiration. The plants himself specially to the investigation-some account of are therefore in the condition of being over-watered. A his latest results. A marked and admitted difference well-known consequence of this is to make them shed between town and country fog is, that while a country their leaves wholesale. Many valuable plants which fog is harmless in a greenhouse, a town fog will produce ought to be well furnished with foliage become perfectly most destructive results.

Bunhill
Row.

Green
wich.

Kew.

East. bourne.

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There is still another action of town fogs, and one sunshine there with, first, the amount in the immediate which I believe is of great importance. I mean its neighbourhood of London, where we are not beyond the power of absorbing light. This power of abstracting effect of town fogs, viz. at Greenwich on one side, and light depends principally on the amount of coal products Kew on the other, and also with a place not far from which the fo contains. The slower-vibrating red rays London, which is beyond the influence of its smoke, can struggle through a fog which is absolutely impervious viz. Apsley Guise, near Woburn. I have also noted the to the more refrangible ones. Even a mist but slightly results obtained at Eastbourne, which is about as far tinged with smoke is opaque to the blue rays, and thus distant from London as Apsley Guise, but in the opposite screens us from their action but as Aitken has lately direction, and is one of the sunniest places in England. shown, the heat rays can pass readily through. This Taking the totals of last year, the table shows that the opacity of town fog to light is, I believe, one of its most hours of sunshine registered at Bunhill Row were 1158, serious and detrimental characters. Animals can no at Greenwich 1255, at Kew 1405, at Apsley Guise 1420, more thrive in semi-darkness than can plants; and, im- and at Eastbourne 1724; but for our present purpose we portant as the red rays may be, still it is undoubtedly the must compare the amounts of sunshine at these places blue rays which are most active in producing the prin- during the winter months—November, December, January, cipal chemical charges going or around us. Experiments and February-and we find that at Bunhill Row there lately made have strongly impressed me with the were 95:8, Greenwich 150, Kew 1717, Apsley Guise 205-9, wonderful activity which light confers on a mixture of and at Eastbourne 268-3 hours of sunshine ; that is, if air and moisture, oxidations which in dullness and Apsley Guise be taken as giving the normal amount, darkness are impossible are easily and rapidly effected Bunhill Row received only half its due amount, and at by aid of a gleam of sunshine, or even a bright dif- Eastbourne there was nearly three times as much sunfused light. It is not possible, I believe, for people to shine as in the City. Now, on comparing the two other remain healthy where this source of chemical activity is periods of 4 months, which are comparatively free from cut off, or even seriously diminished. In addition to the fogs, the amount of sunshine is far more nearly the same loss of physical energy, mental depression is induced at all stations. by the absence of light, the whole tone of the system becomes lowered, and may be a prey to actions which, under brighter conditions, it would have been able to

Aspley resist.

There is another action of light which is potent for good. I mean its destructive action on many forms of March till June

542'4 5814 619'4 5811 736.8 bacteria. Prof. Koch, at the last meeting of this Con- July till October

5193 523.8 613-5 632'5 718.5 gress, pointed out how his tubercle bacilli are killed by even a short exposure to sunlight, and it is now well established how inimical light is to the growth and Mr. Raffles, during the winter of 1887-88, which it development of most kinds of bacteria. I wish I could should be noted was remarkably free from fogs, made a show you in some perspicuous way the enormous power series of observations of the distances to which he could which town fog has of absorbing light, and bring forcibly see from Primrose Hill, and found that looking south on before you the great difference which exists between the the 152 consecutive days from November to March, only amount of light which reaches the inhabitants and build- on 78 days could he see a quarter of a mile, and only on ings of a town, as compared to the amount on an equal | 83 days could he see to the same distance in a southarea free from smoke. A simple actinometer is much westerly direction : this conveys a good idea of the opacity required, and I hope the want will soon be supplied ; but

of our London atmosphere. at present the only records bearing on this point are the We attempt to compensate for the darkness which observations of direct sunshine made at various stations, fogs cause by the use of artificial light, and I have again by the Meteorological Society and Meteorological Office, to thank my friend Mr. Livesey for the information he with the Campbell-Stokes instrument, and some interest: has given me with regard to the extra quantity of gas ing observations, by Mr. H. Raffles, on the distance at burnt in London during a day of fog. He tells me that which objects were visible during a London winter. if a dense fog covered the whole of London, and lasted First, with regard to the sunshine experiments. One all day, the additional amount of gas consumed would be

30 million cubic feet ; but since so extensive a fog as this Hours of Sunshine during the Year 1890.

probably never exists, and certainly never lasts all day,

the actual amount consumed may be correctly reckoned Bunhill | Green

Aspley

at 25 million cubic feet; and if the cost of this be calculated at 25. 6d. per 1000 cubic feet, which is rather below

than above the actual cost, it amounts to £3125; but after January ... 29'9

573 56.9

all, it is not the single days of dense fog that measure the February 42'4 62.8

70-5 105-5 extra amount and cost of artificial light used on account March 713 109-3 1104 133-5

of fog-it is rather the continually occurring dull days and April 12704 1415

137'3 170'1 local transitory fogs which demand an extra supply of May 2157 223'9 223.9 2143

267-9

gas, and this is often 5 to 15 million cubic feet in a day, June

1280 12592 1414 119'T 1653 and gives a total by the end of the winter which is very July 134'1 I 20.6 13999 1413 185-6

considerable. As a standard of comparison, I should August

164'0
153-1
189-5

state that the total consumption of gas in the London September

131.6
153'2
169-5
166:1

2074
October
89:6

district in a day of 24 hours, during the depth of winter, 96-9 1216

125'3 November 234

647

is 140 million cubic feet. December 2'4 0*3 134

Such, then, is an imperfect outline of the chief features 380

and effects of town fogs; and now what is to be said with

regard to the possibility of getting rid of such fogs? This Total 11575 12552 1404.6

14195
17236

question, it seems to me, resolves itself into this : fogs
cannot be prevented from forming over towns; there are,

and probably ever will be, special inducements, in the way station is situated in the heart of the City, in Bunhill Row, of dust particles and products of combustion, for fogs to and it is of much interest to compare the amount of form there ; but whether they must always be dark in

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colour, and loade i with soot and tarry matter, is another together with diminished light, unavoidable during the question. The answer involves not only chemical but prevalency of fog-were proved at Kew to be the safest also social considerations. With regard io the first, my for all plants during the prevalence of heavy fogs. answer is that as long as coal is burnt you will have July 25.

W. WATSOX. dense fogs ; grates, kitcheners, furnaces, may be, and probably will be, much improved, and fires may be stoked in a better way, but that the improvements will be so great that all imperfect combustion will cease I

THE ANATOMY OF THE DOG.' think is improbable ; if this be so, there is only one other alternative, as long as coal is our source of heat: it is to TH

HE dog has played by far the most important part alter our form of fuel and adopt gas and coke ; the soot in the elucidation of the difficult problems of and tarry matters will be then done away with ; the ques physiology and pathology presented by the higher tion of sulphuric acid in the air would remain, but our fogs animal organism. It is by a firm reliance on the would at least be white. There is still the social part of results of experimental researches, conducted largely the question, which is not without serious difficulty – upon this animal, that the modern physician is enabled namely, how to induce or compel people to give up the to form some idea as to the causation of the symptoms use of coal. At the present day it would not be possible of disease in man, and the mode of action of the remedies to do as it is recorded was done in the reign of Edward I.,

which he employs; while the modern surgeon, after a try, condemn, and execute a man for burning coal in the preliminary testing of an operation upon the dog, fearCity of London.

W. J. RUSSELL. lessly proceeds to attack the most deeply-seated tumour,

and to explore the most hidden recesses of the human

organization. What, after all, are the services of friendEffects of Fog on Plants Grown in the Houses at Kew. ship and companionship, or the more menial duties which

are often laid upon the dog, compared with the alleviaThe heavy fogs experienced in the last two or three tion of human suffering and the advancement of human winters injured many plant; in the houses at Kew. When knowledge for which he has served as the passive instruthick fog occurred almost daily, the injury it did to many ment, and this (pace the mendacious asseverations of plants amounted practically to destruction. The leaves fanatical essayists) at the expense of the least possible fell off, the growing point withered, and in some cases, amount of suffering to himself? such as Begonias and Acanthads, the stems also were For these reasons, to the physiologist, the pathologist, affected. Flowers, as a rule, fell off as soon as they the pharmacologist, and the scientific surgeon, a book opened, or whilst in bud. Almost all flowers which ex- which, like the one before us, endeavours to deal with panded' were less in size than when there was no fog. the anatomy of the dog in the same detailed and sysThe Power buds of Phalænopsis, Angræcun, some tematic manner in which the structure of man is dealt Begonias, Camellias, &c., changed colour and fell off as with in text-books of human anatomy cannot fail to be if they had been dipped in hot water.

of the utmost value. To the comparative anatomist it In the Palm-house bushels of healthy.looking leaves, will prove an important addition to the limited existing which had fallen from the plants, were gathered almost series of monographs dealing in detail with vertebrate every morning. Plants which appeared to be perfectly types, while to the veterinarian it will be an indispensable healthy, when shaken would drop almost every leaf. vade mecum, both in study and in practice. Herbaceous plants suffered most, i.e. Begonias, Poin- For the work is done excellently well, a result which settias, Bouvardias, Acanthads, &c. Some herbaceous might be anticipated from the manner in which it has plants, however, did not suffer at all, nor were their been set about. Not only has it been carried on under flowers injured, as, for instance, Cyclamen, Primula, the auspices of a scientific anatomist so well known as Hyacinth, &c. Many, hard-wooded plants lost their Prof. Ellenberger and in a veterinary school where an leaves and were otherwise damaged, viz. Boronias, sone unlimited supply of subjects was available for dissection, Heaths, Grevilleas, Acacias, &c. Protea cynaroides, a but with a far-sighted liberality, for which the Saxon Cape plant with large laurel-like leaves, was much in- Government is much to be congratulated, all the exjured in the temperate house (minimum temperature 40°), penses for material and instruments have been defrayed the leaves turning black as though scalded. The same by the State, and one of the collaborators has been enabled species, however, in another house where the atmosphere to devote his whole time during a period of two years is drier and the temperature a few degrees higher, was entirely to the labour incident upon the preparation of scarcely affected by fog.

this work. As a rule, the plants that were in active growth suffered The book is a large octavo of 650 pages, containmost. Monocotyledonous plants and ferns for the most ing 208 woodcuts, a few examples of wbich are here part were not appreciably affected by the fogs, the injury reproduced. There is, in addition, an appendix of 37 they suffered, especially last winter, being clearly due to lithographed plates, representing in outline frozen seclow temperature. The effect of fog on flowers is remark- tions through the trunk and limbs. A study of these able. Generally, white flowers are destroyed, but there is in itself sufficient to make out the relations of the are some notable exceptions-viz. Masdevalia tovarensis, organs to one another, and the authors have accordingly Odontoglossum crispum, and Angræcum amongst Or burdened the text as little as possible with topographical chids, and Crinums, white Cyclamen, white Hyacinths, details. Histological and developmental references are white Chrysanthemums, &c.

entirely avoided, partly for the reason that the facts are The green leaves of Poinsettia pulcherrima all fell off

, not materially different from those which are found in whilst the red ones (bracts) remained, as also did the other mammals, partly because they have been dealt with, flowers. All Calanthes, of whatever colour, lost their especially for the dog, in other works, and largely because flowers. The buds of the white-flowered Angræcum ses- it was obviously desirable not to increase the bulk of the quipedale turned black as if boiled, whilst those of A. work. References to literature are also for the most part eburneum, also white-flowered, were not injured, and de- , omitted, for although other works have been consulted, veloped properly. These two plants are grown in the it is claimed by the authors that the present account is same house under identical conditions, and they come into bloom about the same time.

"Systematische u. topographische Anatomie des Hundes." Bearbeitet The conditions most conducive to rest from growth-. | Dresden, und Dr. H. Bauin, Prosekt v an der tierärztl.chen Hochschule in based almost exclusively upon original dissections and ties which result therefrom, are, as might be supposed, preparations.

von Dr. W. Ellenberger, Professor an der tierärztlichen Hochschule in viz, a low temperature and moderately dry atmosphere, Dresden. (Berlin: Paul Parey, 189

not ignored by the authors of this book. But they remark It might be supposed that the striking differences, hereon that apart from differences in size, renderboth in size and in shape, which are presented by dogs ing absolute measurements of little value, the racial

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FIG. I -Skeleton of the dog. 2. skull; 0, scapula : c, humerus; d, ulna; ď, olecranon ; e, radius: , carpus; , metacarpus; h, phalanges of fore.

fool; i, pelvis ; i, tuber ischii; k, femur; m, tibia; n, fibula ; 0, tarsus ; p, luber calcanei ; q, metatarsus; ”, phalanges of hind-foot; s, coccygeal vertebræ. The cervical, thoracic, and lumbar vertebræ and the ribs are respectively numbered consecutively.

of races so different from one another as, to take extreme differences are almost entirely confined to the skeleton cases, the greyhound and the pug, would be accompanied and to certain parts of the muscular system, no important by such structural peculiarities as to render a general differences being manisest in the position of the muscles,

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anatomical account of the dog of less value than that of vessels, nerves, and viscera ; and even in crook-legged animals in which racial characteristics are less exagger- ogs, such as the dachshund, in spite of the twisting of ated. The differences which are found, and the difficul- the extremities, the topographical relations of the muscles

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