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per mile..

per mile. The following is a rough esti It will be noticed that very liberal almate of the cost of a gravity plane. As lowances have been made for delays at it is made for comparison with the cost the head and foot of the incline, and for of an equivalent supporting grade, the the friction of the gravity system. The items are assumed very high in order to friction of train, sheaves, etc., has been be sure of covering the expense.

allowed for in determining the inclina1,800 feet of track @ $45,000

tion. And the extra five tons weight of

.$15, 340 counterweight over that of the maximum Counterweight about.

6,000

train is not only sufficient to overcome Steel wire rope....

2,000 Extra work at top and bottom

any resistance due to curvature, but of plane..

1,500 would render some assistance to the locoSheaves, frames, etc.

1,000 motive.

In conclusion, it may be added that in

25,840 For contingencies, etc..

7,160

the construction of such a system due

reference should be paid to the arrange

$33,000 ment of the grades so that the maximum Cost of supporting grade...... 66,000

train, on that portion of the line which The result of the above comparison is arranged as a supporting grade, should may be briefly stated thus: Under the be able to pass over the planes. Or the assumed data, the gravity plane is capa- | arrangement might be made with referble of doing twice the amount of work ence to the division of the trains at the in the same time, while its original cost foot of the planes, in which case it would of construction is only one-half as much be necessary to make two or more trips as an equivalent supporting grade. over the planes for each train.

THE RIVERS OF CHINA.

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THE YANG-TSE, THE YELLOW RIVER, AND THE PEI-HO.

From “Nature." These three rivers form conjointly the ers were in the past, a brief consideration great river system of China. Although of their present condition will prove at the present day each of them runs its that they are laboring towards the same separate course to the sea, there is good end in our own day.

But before proreason to believe that several centuries ceeding to examine them in their consince they were united by a number of joint character, it will be necessary to connecting branches, in a manner some- consider briefly their leading hydrologwhat resembling the junction of the ical features. Ganges and the Brahmapootra in our I.-The Yang.tse—the largest and most own time. Such is the inference to be important of these three rivers-has a drawn from an ancient Chinese_map, course of about 3,000 miles, and drains copied by Alvarez Semedo, a Portu- an area which is variously estimated beguese Jesuit, and which must be assigned tween 750,000 and 550,000 square miles; to a time preceding that of the con- for my own calculations I will adopt the struction of the Grand Canal by Ghenghis mean of these two estimates, namely, Khan in the beginning of the thirteenth 630,000 square miles. Its waters, comcentury.t Linked together as these riv- mencing to rise in February and March,

The author, Surgeon H. B. Guppy, of H.M.S. “Hor. reach their highest level in the month of net,” writing from Yokohama, February 11, says: "1 June or July; and here they remain forward to you by this mail a paper containing

the re- with occasional fluctuations till the end years on the subject of the Yang-tee and the Peiho, of August or the beginning of Septem

Yellow River. Looking on these three rivers as in reality one ber, finally reaching their lowest level river system, I have embodied in one paper all the towards the close of January. "data" concerning them; and have treated them both separately and in their conjoint character. I can answer With regard to the discharge of water for the accuracy of the various testimations, and have of this river, Capt. Blakiston* has esti

t Vide a paper by Mr. S. Moseman on the “ Double Delta of the Yellow River,'' published in the Geographical Magazine for April, 1878.

" Five months on the Yang-tse.”

1877.

Surface

current. Knots per hour.

Cubic feet

Feet.

per second.

mated the average amount carried past the river was at its height; while in T-chang, which is situated at about 960 March, when the river was low, I found miles from the sea, at 500,000 cubic feet as little as three-fifths of a grain per per second ; he founded this estimate on pint. The average proportion of sediobservations made during the months of ment during the twelve months in quesApril and June. When stationed at tion I estimate at four grains in the pint Hankow in the winter 1877-78, a place (a little over half a drachm per gallon). distant about 600 miles from the sea, I This represents a proportion of 1g by set to work to make a similar estimate of “weight,” or (taking the specific gravity the water carried past that city for the of the dried mud at 1.9) of 167 by twelve months included between May “bulk” of the average discharge of 1877 and May 1878. Having taken a water. It is thus easy to obtain the line of soundings across the river and total amount of sediment carried during having ascertained the river's breadth the twelve months past Hankow, namely, (1,450 yards by sextant measurement) at 4,945,280,250 cubic feet : but to allow a point below the union of the Han with for the amount of mud a river pushes the main stream, I commenced a series along its bed, one-tenth must be added of observations on the rise and fall of according to the principle laid down by the river water and on the force of the Messrs. Humphreys and Abbot in the current, which combined with informa- case of the Mississippi. This will bring tion received from the Custom-house and the total annual discharge of sediment from other sources, supplied me with at Hankow up to 5,439,808,275 cubic the necessary data for my calculation. feet, or at the rate of 172 cubic feet per The results are contained in the follow- second. Now, assuming that the draining table :

age area below Hankow supplies the same Average Water-discharge. relative amount of sediment as the redepth.

mainder of the catchment basin, I estiMay 31.. 27 64

846,336 mate the total amount carried down to June 30.. 21

61
896, 293

the sea annually at 6,428,858,255 cubic July 31..

58
1,022,656

feet. Aug. 31..

1,275,381 Sept. 30..

1,018,248

The removal of this amount of sediOct. 31..

622,997 ment from an area of drainage of 650,000 Nov. 30.. 12

308,560

square miles represents a lowering of the Dec. 31.. 1

36
211,584

surface at the rate of one foot (of rock) Jan. 31..

30

141,085 in 3,707 years. This is therefore the Feb. 28.. 14

412,620 rate of “subaërial denudation" of the Mch. 31.. 11

45

396 720

valley of the Yang-tse as far as concerns Apl. 30.. 2

57
670,016

the quantity of sediment removed. Of 12)7,822,502

the proportion of solids in solution, I

have had no opportunity of judging, but

651,875 that the soluble matter is in considerable We may therefore place the average quantity is rendered probable from the water-discharge for the year at Hankow extensive limestone districts traversed by at 650,000 cubic feet per second. Now, this river. estimating the area of drainage above II.---The Yellow River or the Hoang-ho Hankow to be about 1} of the whole has derived the appellation of “China's area, and assuming that the portion of Sorrow” from its frequent destructive the Yang-tse valley below Hankow drains inundations. It runs a course of about off its waters at the same rate as the re- 2,500 miles; but, unlike the Yang-tse, mainder of the river-basin, it follows its lower course has frequently shifted in that the average water discharge for the the course of ages, and although it opens whole river may be placed at 770,000 at the present day into the Gulf of Pe. cubic feet per second.

chili, only a quarter of a century has With reference to the amount of sedi- passed since it emptied its waters into ment carried by the Yang-tse past the the Yellow sea.* The mountainous dissame city, I found, as much as seven trict of the province or Shantung has in grains in the pint (nearly one drachm in truth been the chief means in deflecting the gallon) in the month of July, when Vide Mr. Moseman's paper, already referred to.

3

62 63 53 42

1873.

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39

::::

the waters of this great river on more I found in the water of the Yang-tse was than one occasion during the historical seven grains in the pint, and in the case era from the Gulf of Pe-chili to the Yel- of the Pei-ho—as will subsequently be low Sea and vice-versa.

noticed-fifteen grains in the pint, Sir With reference to the quantity of George Staunton estimates the sediment water discharged by the Hoang-ho I of the Yellow River at over eighty have had no opportunity of personal grains in the same measure of water. observation. We have, however, an es. Even the muddy waters of the Ganges timate not only of the water discharge, do not contain more than twenty grains but also of the sediment, which Sir of sediment in the pint of water. George Staunton supplies us in his ac It is therefore not with any surprise count of Lord Macartney's embassy to that I find the “subaërial denudation" China in 1792. It was calculated that at of the Hoang-ho is estimated at less the place where the British embassy than half that of the Yang-tse, namely, crossed the Yellow River—its junction one foot in 1,464 years. This estimate with the Grand Canal—the water was only refers to the amount of sediment recarried past at the rate of 418,176,000 moved, and yet I cannot but consider it cubic feet per hour, or 116,000 cubic feet as very liable to correction by somo per second. The method employed in future observer. As this is the only calascertaining the quantity of sediment culation that has ever been made, as far was the measurement of the amount of | as I am aware, with reference to the mud deposited from a gallon and three- quantities of sediment aad of water disquarters of water when allowed to stand. charged by the Yellow River, I am perFrom this experiment it was concluded force obliged to accept it as pro tanto. that the sediment was in the proportion

III.—The Pei-ho drains the great plain of ato of the original bulk of the water, which constitutes the province of Peand the annual discharge of sediment was chili. Its length is said to be about 300 assessed at 17,520,000,000 cubic feet. miles, but the lower part of its course

However carefully these observations below the city of Tientsin is so tortuous may have been made, and however near that a distance of thirty miles overland they may approach the actual discharge is converted into fifty by the river. It is of water and of sediment at the time in at Tientsin that the Pei-ho proper and question, it seems to me that one is hardly the Yu-ho unite together to form the main justified in accepting the result of a single stream; the latter is generally known by observation as typical of the average Europeans as the Grand Canal, but as a state of things throughout the year; matter of fact the canal joins the Yuand yet Sir George Staunton's estimate ho about 150 miles to the southward. has never, as far as I am aware of, During the three winter months-Debeen questioned. A single glance at the cember, January, and February—the Peiforegoing table will convince one of the ho is usually frozen over, the ice having little dependence that can be placed on a a thickness of about eighteen inches; in solitary estimation; it will be there seen the same season there is generaliy a large that the Yang-tse discharged nine times quantity of ice in the Gulf of Pe-chili, as much water when at its highest level which may completely fill up the head of in August as it did during the month of the gulf. January, when its waters occupied thei With reference to the water discharge lowest level.* Or if the question of sedi- of this river, I. was enabled while winterment is considered, to which the same ing at Tientsin during the season 1878objection would apply, I have the great- | 79, to collect some “data” for its estimaest diffidence in accepting Sir George tion during the four months from DecemStaunton's estimate as being of any ber to March. Although my estimate value, except as a trustworthy result o strictly applies to but a third of the year, a single experiment; and yet, even con- still from the limited rise and fall of the sidered as the maximum of the whole water during the different seasons (it year, the result is rather a startling one. never exceeds six feet) I feel pretty conWhile the greatest amount of sediment fident that it fairly represents the aver* In the case of the Ganges at Ghazepoor the propor

age rate of discharge during the whole tion is as 1 to 14.

* Vide Nature, vol. 18, p. 288. Vol. XXIV.-No. 145.

current,

Cubic feet

Feet.

1879.

year. The breadth of the river at the January and February it did not equal a place of observation below the city of grain in the pint.) This represents a Tientsin was 280 feet. The following proportion of no by weight,” or table contains the results of my calcula- 33427 by “bulk”of the average discharge tions :

of water; and following the same method Surface Average Water discharge of calculation as 1878. depth.

was employed in the Knots per hour.

per second. case of the Yang-ise, I estimate the anDecember 1%

14

6,355

nual discharge of sediment for this river January..

141

4,389 at 80,000,000 cubic feet. February.

16

9,684 Now the removal of this bulk of maMarch...

14

10,592

terial from an area of drainage, which I 4) 31,020

estimate at 55,000 square miles, repre

seuts the lowering of the surface of one 7,755 foot in 25,218 years.

This is the rate of We may thus place the average dis- “subaerial denudation” of the Pei-ho charge of water for the whole year at basin, omitting of course the question of about 7,700 cubic feet per second. the solids in solution.

Now with regard to the amount of To show the rank that these three sediment carried past the city of Tient- rivers hold in the fluvial system of the sin : I found the average quantity globe, I have subjoined a list of fourteen during the four months in question other rivers which gives the quantities to be about five grains per pint. (It of water and sediment discharged by varied much at different times, for I each, as well as the rate of subaerial defound as much as fifteen grains in the nudation, as far as I have been able to middle of March, while in the months of ascertain.

Water discharged

Sediment per

Subaërial denuda

tion.

per second.

annum.

Cubic feet.*

Cubic feet. Amazon...

2,458,026 Congo...

1,800,000
(By Behm and Capt.

Tuckey.)
Yang-tse...

770,397
6,428,800,000

1 foot in 3,707 years.
(By myself.)
(By myself.)

(By myself.) Plate....

700,000
1,543,500,000

1 foot in 29,400 years. (By Mr. Higgin and (By Mr. Higgin.) (Calculated from Mr. Mr. Bateman.)

Higgin's estimate.) Mississippi.....

618,000

7,474,000,000 1 foot in 6,000 years. (By Messrs. Humphreys (By Messrs. Humphreys (By Mr. Croil.) and Abbot.)

and Abbot.) Danube....

300,321
1,255,500,000

1 foot in 6,846 years.

(By Mr. Ch. Hartley.) Shat-el-Arab....

295,461 Ganges, at Ghazpoor.. 203,485

6,368,000,000

1 foot in 2,358 years. (By the Rev. Mr. (By the Rev. Mr. Everest.)

Everest.) Indus...

199,476 Atrato.

185,274 Nile..

130,032 Yellow River..

116,000

17,520,000,000 1 foot in 1,464 years. (By Sir George (By Sir George Staunton.)

Staunton.)
Rhone...

91,935
594,000,000

1 foot in 1,528 years. 69,741 Po..

61,263
405,420,000

1 foot in 729 years.

(By M. Lombardini.) Pei-ho....

7,755

80,000,000

1 foot in 25,218 years. (By myself.)

(By myself.) Thames, at Kingston..

2,300

1,865,900 1 foot in 9,600 years. (By Prof. Prestwich.) (Huxley's “Physio (Huxley's “Physio

graphy.”)

graphy.") Where not otherwise mentioned I have obtained my information of the discharge of water and sediment from the "Earth,” by Elisee Reclus.

† This estimate also includes the solids held in solution.

Rhine.....

We have now the necessary" data” for low Sea during the preceding ages. In considering these three rivers in their either event the union of these three conjoint character. Together they drain rivers would follow. an area of 1,105,000 square miles; they Such being the case, it may be interestdischarge a body of water equal to ing to speculate on the time required by 894,000 cubic feet every second; and these rivers to fill up the seas into which they carry down every year to the sea they discharge their sediment. Sir 24,028,500,000* cubic feet of sediment, George Staunton estimated that at the which represents a rate of subaerial de- rate the Hoang-ho was discharging sedinudation equal to the removal of one ment it would fill up the Yellow Sea and foot of solid rock in 1,687 years.

the gulfs of Pe-chili and Lian Tung in If we look upon the Yang-tse, the ! 24,000 years; but M. Elisée Reclus is of Yellow River, and the Pei-ho as labor- opinion that this estimate ought to be ing, with the assistance of the gradual ele- doubled, as the Yellow Sea is much vation of the sea border, which is at deeper than Sir George Staunton stated present going on, to extend the territory it to be (20 fathoms). On carefully exof China seaward towards her ancient amining the latest charts of these seas I coast-line-represented by a line running am inclined to consider that this estimate from Kamtschatka through the Kurile cannot be assailed on this point, as my Islands, Japan, the Loo-choo group, For- own determination of the average depth mosa, down to the Malay Archipelago; † is 22 fathoms. and carry ourselves forward into the We will now attempt to gauge the future when such task is completed and the time that the three rivers in question the waves of the Pacific beat once more would require to fill up, by the sediment against this old sea border, we shall not they deposit the portion of the sea which have much difficulty in picturing to our is included by the gulfs of Pe-chili and selves what will then be the state of Lian Tung,' the Yellow Sea, and the matters. In the place of the gulf of Eastern Sea north of the 29th parallel Pe-chili and the Yellow Sea there will and west of the 126th meridian. I have be vast alluvial plains traversed by the placed the total surface area at 200,000 waters of the Yang-tse, the Yellow English square miles, and the average River, and the Pei-ho; but before depth at 26 fathoms; and following Sir the ancient coast line is reached they George Staunton's mode of estimation I will have joined to form one great river find that it would take sixty-six days and one united delta. If the Yellow to form an island a mile square reaching River confines itself mostly in future up to the surface of the sea. At this ages to its course into the gulf of Pe-chili, rate it would require 36,000 years to form that gulf will be filled up in process of all the sea in question into dry land, suptime; and the Hoang-ho winding along posing of course that there was no elethrough the bed of this obliterated sea vation or depression of the sea-bottom will, after being joined by the Pei-ho, during that period. But the recent forturn its course southward, deflected by mation of several islands and shoals in the Corean peninsula, until it meets at the Yang-tse estuary, the occurrence of length its sister stream. On the other raised beaches and marine remains at hand, should the Yellow River be mostly Hang-chau, Wusung, and Chefoo, with occupied in future in advancing its other similar evidences, demonstrate southern delta it will join the Yang-tse that there is an elevation of the coast at a period much less remote from the going on at present; and, in that case, it present; and their united waters will will require considerably less than 36,000 pursue an easterly direction subsequently years to form the sea into terra firma. to be joined by the Pei-ho, which will Perhaps Sir George Staunton's original have been gradually finding its way estimate for the Yellow River may not be through the gulf of Pe-chili and the Yel- far wrong when applied to the whole sea • In “ Page's Advanced Text-book of Geology,'

in question. Stannton's estimate of the sediment discharged by the Yellow River has been erroneously applied to all " the

In Western Australia the construction great Chinese rivers."

+ Vide a paper on this subject, by Mr. A. S. Bickmore, of a telegraph line to Roeburne is under read before the North China branch of the Asiatic So. ciety in November, 1867.

consideration.

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