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NIGHT

COUGH

IN WINTER.

HOUSANDS are troubled with this, many to su

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an extent as to render them incapable of fulfillir, their daily duties. The SIMPLEST and MOST CERTAIN Remedy is a GAS FIRE burning low the bedroom all night. The Cost is very small, the Rel is INSTANTANEOUS. Special Gas Fires suite

for this purpose may be obtained from

Fletcher, Russell & Co., Ltd.

THYNNE STREET, WARRINGTON;

30 KING STREET, MANCHESTER;

115 CHEAPSIDE, LONDON, E.C.

AND

SEE SPECIAL FIRE LIST PATTERNS,

HN, KN, HR, & KR.

The two first are also made with Boiling-burners on the top. for Nursery use and special emergencies.

A Large Stock kept for immediate Delivery in case of emergency.

THURSDAY, JANUARY 12, 1893.

AMERICAN MECHANISM.

lern Mechanism. Edited by Park Benjamin, LL.B., 1.D. (London and New York: Macmillan and Co., 92.)

order to appreciate this volume thoroughly, it is
necessary in the first instance to consider the reason
s existence. Appleton's " Dictionary of Engineering,"
American book, was published in the year 1851,
was the first to gather in cyclopedic form descriptions
roducts of American mechanical industry. Some
y years afterwards it became necessary to bring the
: up to date, and its complete reconstruction was de-
d upon. The editor observes that no previous work
technical character had so signally, and so quickly,
onstrated its own usefulness; it rapidly became a
gnized standard of American mechanical practice.
ng, however, to the great progress made in mechanical
ntion, and the marvellous rapidity with which electrical
nce has advanced, a new record of the results has
›me necessary, and hence the present volume.

he list of contributors includes the names of eminent
, well known in this country for their high attain-
ts in the different branches of mechanical and
trical engineering, forming a sure guarantee that
information to be gleaned from the pages is valuable
accurate. It would be impossible in the space at
disposal to notice more than a small part of
contents. Some interesting information is to be
d on the subject of aerial navigation, more particu-
y the interesting experiments being carried out by Mr.
am S. Maxim. Commenting on Prof. Langley's state-
it, that with a flying machine the greater the speed
less would be the power required, Mr. Maxim says:
navigating the air we may reason as follows: if
'make no allowance for skin friction and the resistance
the wires and framework passing through the air-
se factors being very small indeed at moderate speeds
compared to the resistance offered by the aeroplane
may assume that with a plane set at an angle of 1 in
and with the whole apparatus weighing 4000 pounds,
push of the screw would have to be 400 pounds.
pose, now, that the speed should be 30 miles an
r; the energy required from the engine in useful
ct on the machine would be 32 horse-power (30
2640×400 = 32). Adding 20
s=2640 feet per minute,
33,000
cent. for slip of screw, it would be 38'4 horse-power.
pose, now, that we should increase the speed of the
hine to 60 miles an hour, we could reduce the angle
ae plane to 1 in 40, instead of 1 in 10, because the
ig power of a plane has been found to increase in
>ortion to the square of its velocity. A plane travelling
ugh the air at the rate of 60 miles an hour, placed at
ingle of 1 in 40, will lift the same as when placed at
The push of
10, and travelling at half this speed.
screw would therefore have to be only 100 pounds,
it would require 16 horse-power in useful effect to
e the plane. Adding 10 per cent. for the slip of the
w, instead of 20, as for the lower speed, would

increase the engine power required to 176 horse-power. These figures, of course, make no allowance for any loss by atmospheric friction. Suppose 10 per cent. to be consumed in atmospheric resistance when the complete machine was moving 30 miles an hour, it would then require 422 horse-power to drive it. Therefore at 30 miles an hour only 3.84 horse-power would be consumed by atmospheric friction, while with a speed of 60 miles an hour the engine power required to overcome this resistance would increase eightfold, or 307 horse-power, which, added to 176, would make 48'1 horse-power for 60 miles an hour."

Mr. Maxim goes on to observe that his experiments show that as much as 133 pounds can be carried with the expenditure of 1 horse-power, and under certain conditions as much as 250 pounds. It will be evident, therefore, that the question of motors is all important, and that the total weight per horse-power developed must be as low as possible. It is stated that the greatest force can be obtained from a compound high-pressure steam engine using steam at 200 to 350 pounds pressure, and such engines have been constructed weighing 300 pounds; the horse-power of these engines is not stated.

It will be interesting to watch the outcome of these investigations. They indicate that much information is being accumulated, and that sooner or later a successful aerial machine will be forthcoming.

The question of armour plates has long vexed the soul of the British Admiralty; many very costly trials have been carried out in order to find the most suitable plate for the service. All these data have probably been known in the States, and that country must have benefited by them. Under this heading we find much information in the book, American experiments being quoted and illustrated. Naturally, the Americans wish to make their own plates, and wisely endeavour to do so by rolling only, to do without the heavy expense of forging. These experiments show that the high-carbon nickel Harveyed plate As a result of is undoubtedly the best plate ever tested. An excellent full-page these trials, orders have been placed for plates for the cruisers under construction. engraving is given of the U.S. armoured battle ship Indiana, and to judge by the blackness of the smoke she is not using Welsh coal! The article on steam boilers is well written, and very complete, containing much useful information. Among the many types of boilers illustrated there is a good print of the Yarrow torpedo boat boiler. We miss. however, the familiar Thornycroft boiler, and note an American water tube-boiler for fast launches very like the Thornycroft in the arrangement of the tubes.

The boilers for marine purposes are purely of the British type, and there is nothing of importance to note on this subject beyond the many experimental results recorded.

Further on in the book there is an interesting description of railway-car heating. We are told that car-heating, in the usual acceptance of the term, has come to mean the heating of railway cars by the use of steam from the This is important, showing as it does the locomotive. direction in which American railway companies are Genermoving in the solution of a problem at present occupying the best attention of engineers in this country.

M

ally, we are told, the systems consist of a separate hotwater circulating system in each car, in connection with a heater, fed by steam from the locomotive, by a continuous train pipe running the length of the train, and coupled together between the cars by flexible hose-pipes and universal couplings; the Sewall steam coupler being generally used. Another important railway necessity is the continuous brake. Under this heading the latest form of Westinghouse quick-action automatic brake is described. In the original design the brake is applied by the engine-driver allowing a little air to escape from the train pipe, lowering the pressure, and thus applying the brake by the automatic action of the triple valves. It is evident that the vehicle next the engine will feel this reduction first, and its triple valve will work before that on the second vehicle, and so on. On trains of ordinary length this very slight difference in time between the brake's application on each vehicle is of little consequence, but when this automatic brake is fitted to a long goods train it becomes a serious matter. The length of a goods train of fifty American cars is 1900 feet, and the brake should act instantaneously to be perfect. The new triple valve is itself designed to discharge air from the train pipe; so on the driver opening the driver's valve, allow ing air to escape to apply the brakes, the reduction of pressure operates the triple valve on the first car; this lets out more air, and so on through the train, the brake on the last car, 1900 feet away, being operated in 25 seconds after that on the first car.

The vacuum automatic brake is not described or illustrated. This brake is now being more and more brought into use an i for general purposes it appears to be simpler and less liable to get out of order than its competitors.

until it reaches the point where the trolley of one c motor cars is in contact. Here it divides, and a p passes down through the trolley to the motors thence to the rails forming a return lead to the rea brush of the generator. The main portion of current passes on to feed other cars upon the line same manner, each car taking the quantity of c necessary to develop the required power. There a the present time nearly 500 electric railways in Ame and taking the results of twenty-two electric trolley we find that the expenses vary per car mile from = cents to 7.89 cents, the highest and lowest respect A view is given of the electric street railway at War ton, D.C.; the overhead conductors being not unsightly.

On electric welding there is also much inferm the Thomson process being very fully described consists briefly in completing the electrical r through the parts to be welded together, the res being sufficient to heat the parts so as to weld them. being assisted by pressure.

The Bernado process is not described; in this pr the work to be welded is connected to one terms the dynamo. The positive terminal being conte with a carbon rod, held in a portable insulated b the carbon rod is then placed on the work, and mediately withdrawn slightly, thus forming a where the metal melts, and with skill much done.

The locomotive practice in America has long te interest to locomotive engineers in this country, the many differences in design and practice. A good résumé of American practice is to be found memoir under this heading. A useful table is showing a few leading dimensions, weights, &c., of engines in use. Take, for instance, the express ger engine, a four-coupled bogie engine, the being 20 inches in diameter and 24 inches stroke driving or coupled wheels are 72 to 78 inches in dan The weight on coupled wheels is 75,000 pounds tons), the total weight of the engine being 116,000 ** (5178 tons), and that of the tender 72,000 pounds tons. Comparing these data, we find that the At engine is heavier than an 18×26 cylinder British p and not so powerful, assuming equal steam prest the tender is light in a similar comparison, p

A considerable part of the volume is taken up with the applications of electricity, for lighting and motive power purposes generally. On dynamo electric machinery much has been written and well illustrated. The reader is taken step by step from the rudiments of the subject to its latest applications, from a description of armatures to the arrangements of the field-magnets, then to the varying designs of dynamos, including most of the known machines. The same may be said on the treatment of the electric motors. Under the head of the transmission of power there is more useful information to be found, this being all the more interesting, because of the proposed use of electricity as a means of transmitting some of the power of Niagara to distant towns. There is, how-carrying less water. The reputed weight of trains -ever, something wanting under the heading of electrical measuring instruments. The only ones mentioned are Weston's volt and ammeters. At the present time the street tramways of this country are in an uncertain stage as far as motive power is concerned; horse-power is admittedly expensive; the steam locomotive seems to have got into disrepute; the cable and electric traction appear to be struggling for the mastery. It is interesting therefore to read the memoir on electric traction in this volume. The accumulator system is just described, but the overhead cable or trolley system takes up the greater part of the space, so it is safe to assume that the latter is more generally in use, the principle of which is as follows: the current starts from the positive brush of the dynamo, passing out to the main conductor, suspended over the middle of the track, and along this conductor | 76 square feet, or four times the area of the 5

given in the table is of little use, because the spee not given, and for this reason comparisons ca made.

The paragraph on locomotive boiler constract far too short; many interesting details might have added. It is stated that the circular smoke-t plate is a conspicuous difference between the pr of the two countries, being purely American, the Midland Railway Company have, amongst used the arrangement for some time. Owing enforced use of anthracite coal in certain parts, peculiar designs of locomotive boilers have been the Wootten boiler being probably the most of All, however, have particularly large grate areas » in the case of the Wootten, may in some case:

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nt British engines. An illustration is given of an ine of this type, as well as a full-page engraving of ompound locomotive with a similar boiler. This pound is very different from the Webb or Worsdell nes common in this country, being the design of the erintendent of the Baldwin Locomotive Works. The aders are outside the frames-there are two on each viz. one high-pressure and one low-pressure. The ibution of the steam being effected in each pair by piston valve, each pair of pistons is connected to crosshead, coupled in the usual way to the wheels. it compound engine of the " Webb" type is also illusred. This engine was constructed to Mr. Webb's #gns in this country for the Pennsylvania Railway in 1. It is stated that the results of experiments showed aving of fuel over the ordinary engine of from 20 to per cent.

this book is so full of interesting matter of so varied iture that it would be possible to prolong this notice beyond the space available. Take, for instance, cultural machinery; the Price ploughing outfit is cal of the rest, consisting of a traction engine drawing gangs of three ploughs, the twelve ploughs cutting en feet wide. The subject of milling tools is also of rest, because it is only during the last few years ish engineers have used this means of shaping als, the system having been brought into general use he States.

'nder the head of the manufacture of steel all the al processes are described. We are informed that the itworth compression process is only partly successful he formation of sound ingots; with this statement we not agree; the Whitworth steel ingot after comssion is certainly sound throughout.

aking into consideration the great mass of informacontained in the 900 odd pages of this work, and the eral excellence of the matter accumulated, it is only to congratulate the editor on the completion of a k which must prove useful to many, and which should I a place in all technical libraries. The volume goes to describe modern American mechanism, exhibiting latest progress in machines, motors, and the transsion of power.

SEEDLINGS.

Contribution to our Knowledge of Seedlings. By the ight Hon. Sir John Lubbock, Bart., M.P., F.R.S., .C.L., LL.D., with 684 figures in text. In two olumes. (London: Kegan Paul, Trench, Trübner nd Co., Ltd., 1892.)

EEDS and seedlings have occupied the attention of Sir John Lubbock for a somewhat lengthened od. They have formed the subject of various comications, on his part, to the Journal of the Linnean ety and other publications. In the present volumes, estly styled a "contribution," he gives us the details which his inferences have been founded.

he physical and chemical aspects of germination are ely passed over, but the morphological phenomena The reated with a fulness never before attempted. or has availed himself of the resources put at his disl by the authorities at Kew, where the larger propor

tion of the seedlings described were grown expressly for the purpose. The Natural History Museum and the Cambridge Botanic Gardens have also been requisitioned, and much help has been rendered by capable assistants, whilst the services of Sir Joseph Hooker and Mr. Rendle, in looking over the proof sheets, are duly acknowledged. A work of such dimensions, crowded with detail, could hardly have been produced without such zealous co-operation. Nevertheless unity of plan and uniformity of treatment are conspicuous throughout, and thus comparison is readily effected.

Some previously published papers in the Journal of the Linnean Society, dealing with the causes which determine the form of leaves and cotyledons, are reprinted as the introduction to the treatise. The conclusion therein arrived at is that the form of the embryo, and especially that of the cotyledons, is essentially influenced by the form of the seed. On p. 78 the author begins the detailed examination of seedlings taken from almost all the orders of flowering plants. Five hundred and thirty succeeding pages in the first volume, and five hundred and eighty-eight in the second volume, are thus occupied. This little bit of statistics will serve to show the amount of detail which is contained within these volumes. The plan adopted is to give, first of all, a general sketch of the principal modifications exhibited by the fruit and seed in each order. Then follows a more detailed description of the seed and of the seedling plant in various representatives of the order. As these descriptions are identical in plan throughout, they are of great value to the student of comparative morphology. Naturally some orders are much better represented than others, but sometimes the omissions are rather unfortunate. In the genus Araucaria, for instance, seedling representatives of which are common in botanic gardens and nurseries, the diversities in the form of the seedling and in the mode of germination are very remarkable. Characters" " derived from the seedling plant have been recognized as of the highest importance for classificatory purposes since the time of John Ray (1682-1703).1

66

But whilst this is generally the case, such extraordinary exceptions as that mentioned in Araucaria are very noteworthy, and not less so because the genus in question is one of the very oldest of which fossil botanists have cognizance.

Myrtacea and Sapindaceæ are remarkable for the extremely diverse character of the embryo in different genera, and of which due note is taken in Sir John Lubbock's book. In Rosacea, on the other hand, the diversity is much less, nor is there any important morphological difference in the seedlings of the great order Compositæ, and scarcely more in Umbelliferæ, so far as they are known. These are facts of great significance with reference to the theories of inheritance and relative antiquity of groups.

It may not be without interest to cite what Ray says on this matter:"Floriferas dividemus in dicotyledones quarum semina sata binis foliis anomalis, seminalibus dictis, quæ cotyledonum usum præ tant, e terra exeunt vel in binos saltem lobos dividuntur, quamvis co- supra terram foliorum specie non efferant ; et monocotyledones quæ nec folia seminalia bina efferunt nec lobos binos condunt." Thus Ray not only recognized the pre.. sence of one or of tw cotyledons, but also their nature and their epi- or hyp geal condition. As Ray has been mentioned, it is cer ainly not inappropriate to allude to Grew also, for the first chapter of his "Anatomy of Plants" (1682), and the whole of the fourth book is devoted to the seeds and seedlings and in perusing them the reader will perceive that Sir John Lubbock has in a few cases been anticipated by his celebrated predecessor.

The gradual evolution of the perfect plant from the seedling is indeed a subject of great interest to the phylogenist, although it is difficult-nay, impossible-to separate those appearances which are merely hereditary from those which are the result of varying outward conditions, the more so because analogous conditions must have influenced the ancestors in past times even as they affect their successors now.

Amid such a mass of detail it is difficult to pick out points worthy of special note. We select two only out of many scores that might be mentioned. Some Onagrads are remarkable for the intercalary growth which takes place in the cotyledons, of which several illustrations are given in Sir John Lubbock's book. They call to mind the experiments of the late Prof. Dickie, who, by suppressing the plumule of seedling castor-oil plants, succeeded in inducing the cotyledons to continue their growth and to assume dimensions much greater than that which is habitual to them.

The small tubercles on the root of Myrica californica (vol. ii. p. 523, Fig. 663) have, so far as we know, not previously been observed. The author compares them to those found on Alnus cordifolia, and it would be interesting to ascertain whether these outgrowths are caused by an organism analogous to Schinzia alni, as described by Woronin, or to that which induces the peculiar tubercles on the roots of Leguminosa, recently studied by Prof. Marshall Ward.

Monocotyledons generally have been rather badly treated by the author, although such genera as Potamogeton, Aponogeton, Orontium, and other Aroids, and Palms (of which not a single illustration is given) would have furnished examples at once interesting and easily

accessible.

The work includes nearly seven hundred illustrations, faithfully executed, and very valuable to the student. The bibliography, in spite of its occupying no fewer than thirtyeight is the weak part of the book. Some of the most pages, important references are omitted, and whole series of species whose mode of germination has been recorded and sometimes figured, have been passed over This only shows how colossal has been the task which Sir John Lubbock has set himself. We do not think the worse of the sun for having a few spots on his disc, nor are botanists at all likely to disparage this work because further research might have added a few more illustrations. As it is, it forms one of the most substantial and important contributions to botanical literature that have ever emanated from the press. It must continue to be a standard book of reference for generations, and it will, we hope, stimulate observers, according to their several opportunities, to prepare similar monographs on the various organs of plants.

MAXWELL T. MASTERS.

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of the visitation in the clear light of hard figures, a trace its onset and decline in mathematical curves work is of value in more than one direction. It pres for future generations a definite record of an epide greater precision than the impression left on the ... the physician: it enables a comparison to be between our own experience and that of other e by the sifting and sorting of facts which it necess may lead to the discovery of relationships wit diseases which may prove of no small value pathologist.

This work has been done for influenza by Dr. L. a very thorough and painstaking manner from the collected under the supervision of the Registrar-Ge It says much for the completeness of our regi system in London, that it is possible to compe them such tables and curves as those with which presented in this work, nor are such materials able from any other city in Europe. The only o whose statistics have been found by Dr. Dixey suf accurate for comparison with our own are Pa-Berlin.

Dealing first with the epidemic of 188 shows in Table 1 the rise and progress of the in London, as indicated by the weekly returns t cases, grouped according to the seven age periods a in the official returns. Table 2 gives us, so far returns of the period permit, the similar figures : epidemic of 1847-48. The similar characters of epidemics are strikingly illustrated: in both wes same extreme suddenness of rise, and the same fr of decline, rapid at first, but becoming gradually In the next two during the succeeding months.

are included similar figures for Paris and Berlia these, and in Table 5, the author gives an araji the meteorological conditions accompanying the refall of the epidemic in the three cities. These interest as showing how little influence the weare on the course of the disease as a whole.

In the tables which follow-which are pertin greater interest than any of the others Dr. De compiled-the effects which influenza has event: the mortality from other diseases in London an cities are shown. These effects are of two kina fluenza may aggravate the mortality of pre-exis ease such as phthisis or heart disease, or diseases bronchitis or pneumonia may occur as complicat influenza and swell its death-roll. It is interest observe that whereas in 1847-48, which was in all s a more fatal epidemic than that through which«. just passed, bronchitis showed the most extrem: parture from the normal mortality, pneumonia ho place in the late epidemic, while bronchitis falls second rank. In this connection may be meant point of much interest illustrated in Tables 10, 11which deal with the age incidence of influenza concomitant diseases. It is possible to dra showing the special age incidence of each, ar curve has its own special features. Now dur influenza epidemic the pneumonia curve is four modified so as to take on some of the characters influenza curve, thus affording corroborative evide a conclusion already reached both in this country

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