160 ADXISSIONS AND ELECTIONS. [Minutes of

Associafe IlIe1r~71err. HORACEALLEN, Stud. Inst.C.E. GEOXGEDALLAS MARSTOX, Stud. Inst. JAMES ATEINSON. C.E. ARTHUR BARCLAY. CHARLESEDWARD MASTERMAN. CHARLESWILLIADX BARNETT. JOHXNETHVEN. FELICIANOMENDES DE MESQUITA \vILLIAM BURTON8bVILLE IIILLS, BARROS. Stud. Inst. C.E. WILLIAM BASHALL, Jun., Stud.Inst. WILLIAU PCRCELLOWEILL, Stud. C.E. Inst. C.E. PERCYBENHAB~, Stud. Inst.C.E. CAHILOGUILLERXO PARDO,Stud. EDWARDROBERT BIRCH, B.A., B.E., Inst. C.E. Stud. Inst. C.E. CHARLES DONALD NAPIERPAREEL HARRYBIRD. HENRYPARKES, Stud. Inst. C.E. WILLIAMNISBET BLAIR, Stud. Inst. WILLIAM MORROPEARSE. C.E. CHARLESBERKELEY PENLINGTOB, CARL RODERIQUELOUIS MENNI BONN. Stud. Inst. C.E. THOXASSMITH BRIGHT,Stud. Inst. WILLIADIFRANK PETTIGREW, Stud. C.E. Inst. C.E. CHARLESEDWIX BROWN. WILLIAXHEXRY RADFORD. WILLIAMHENRY BURR. WILLIAXREID. JAMESBUTLER. PETERROBERTS. ALBERTHAVELOCK CASE. HENRY GEORGEARCHIBALD ROUSE. ALFRED CREER. HEXRYROYLE. FITZHERBERT RUXTOXDESPARD. ROBERT ALLENWILLIAM SNINNERTON. HEXRYFRANCIS DOREY, Stud. Inst. ALBERTHARRISON TURNER. C.E. PERCYJOHN WATES. QEORGEHOLLAND ERSKINE, Stud. Inst. THOMASDUNClN WEIR, Stud.Inst. C.E. C.E. HARRYF~ANCIS. I~AU~IICEFITZGER.4LD WILSON, Stud. JAMESFRENCH. Inst. C.E. ROBERTMACNISH GALE. JOHN i%CKWORTH WOOD. RICHARDHACK. FREDERICKADLARD WRIGHT, Stud. GEORGE HOWARDHARBISON. Inst. C.E. LLOYDHASSELL, Stud. Inst. C.E. ROBERTW.4DE WRIGHT, Stud.Inst. PERDINANDHUDLESTON. C.E. WILLIAMOWEN LGCAS.

Associate. WILLIAVWAKEFORD.

‘‘ Speed on .” BY FEANCISROUBILIAC CONDER, M. INST.C.E. THEamount of resistance tothe propulsion of vessels through narrowchannels, due to the size, the form, andthe surface of the channel,has not hitherto been fully studied. Thatthis

Downloaded by [ University of ] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. PLATE 1

e% 120'.0" X 20'.0'

FORT H AND C LVD E. 1768. GLOSTER AND BERKLEY.

1793. CALEDONIAN. 1803.

WILTS AND BERKS. , AND PAISLEY. 1796. AMSTERDAM. 31865. 1803.

45'"'' X 5'.0" 50'.0"x R'.O'

GRANDJUNCTION. MONKLAND 17 DD. NORTH HOLLAND. 1770. 1825.

K.CONDER, DEL? DownloadedF by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] CONDER ON SPEED ON CANALS. 161 resistanceincreases in some ratio tothe diminution of free mater-way is known. In the ‘Minutes of Proceedings’will be found thestatement that asteamer which attained a speed of from 16 to 18 miles an hour at sea, could not make more than from 8 to 9 miles per hour in the narrowest part of the Clyde ; 1 and that a boat which had a speed of 10 miles per hour in the Liffey, could not make more than 7 miles per hour in the Royal Irish .2 The instant acceleration of aboat on passing into deeper water, which was mentioned in the debate cited, is well known to all boating men. But no formulafor determining the proportion is to be found in engineering text books. It was the advice of the Author, on being consulted on one of the most important hydraulic projectsof the day, that there should be instituted, in the firstplace, so thorough an investigation of the mainscientific questions involved as to leave no point open to hostiIecriticism. Among the specialsteps recommended to this end was “ the commencement of a series of experiments for deter- mining the form of cross:section best suited for canal navigation.” The recommendation nothaving beencarried out, the Author has endeavoured to apply to theelucidation of the question certain known facts as to the movement of water in channels of various forms, and as to the movement of vessels in open waters. As to the first, the experiments of Darcy and Bazin have been chiefly of use; and as to the second, those of the late Mr. W. Froude, N. Inst. C.E., on the wave-making resistance of ships. Since the commencement of the inquiry, its importance hasbeen accentuated by the extraordinarydegree of attention that has been excited bythe Suez Canal, and by the remarkablephenomenon of the retardation effected in thepassage of vessels, although not amount- ing to an average of five each way per day. The average time occupied in actual movement through the canal hasincreased from seventeen hours pership in1876, to eighteen hours sixteen minutes in 1881, and to eighteen hours fifty-seven minutes in 1882; the speed slackening from 5 * 88 to 5 -47and 5 27 miles per hour. The time passed in the canal by each ressel has risen from thirty-nine hours in 1876, to fifty-three hours forty-six minutes in 1882. And a very recent Report cites three cases of English mail steamers detained for seventy-one hours each in the canal. It is thus un- deniable that the question of canal capacity for transport assumes

* Minutes of Proceedings Inst. C.E., vol. xxvi., p. 20. * Ibid., vol. xxvi., p. 32. TILe Times, 20th September, 1883. [THE INST. C.E. VOL. LXXVI.] M Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 162 CONDER ON SPEED ON CANALS. [Minutes of a foremost rank among the practical engineering problems of the day. In theabsence of direct experiment, the only method available for the purpose of research is the comparative method. By this, mathematical considerations may beillustrated toa certain extent; and it may be at all events hoped to get so far as to determine where direct experiment becomes indispensable. A vessel in its progress is continually displacing a mass of water equal to its own submerged bulk. This mass is usually calcu1at.ed as proportional to the greatest immergedcross-section of the vessel ; an approximationsufficiently close for the presentinquiry. In open water, the vacuum that would otherwise be left in the wake of the vessel is filled by the water rushing infrom all sides. It is unnecessarynow toinquire how this movement of thewater affects the speed of the vessel, as the ordinary performance of the latter inopen water is taken as the unit of comparison. Whenthe movement of a vessel takesplace in a restricted channel, the case is altered. There is no longer an indefinite supply of water all round thevessel to rush into the hollow at the wake. That hollow is filled, eitherby water which follows the movement of the vessel through the canal, or by that which Aows as a counter current, being driven by the head due to the wave caused by the vessel. The first of these two actions is so limited that it may be neglectedexcept in river navigation. The back- ward current, taken alone. will be directly as the speed and as the cross-section of the vessel, and inversely as the free water-way, or excess of t,he cross-section of the canal over that of the vessel. Thus a vessel moving through a restricted channel has to on- counter an opposing current which is a function of her own move- ment. Her speed will be the resultant of her proper motion and of that of the current, inso far asit affects her, and willbe, roughly speaking, the difference of the two speeds. It is thus possible to obtain,subject to further elucidation,a general formula for the retardation of a vessel in a canal due to the back-current produced by her own movement.

Let A = the cross-section of the canal ;

a= 7) 7, ,) ,) vessel; A n = -. a’ V = the speed in open water ; y = the back-current in thecanal ; X = the speed of the vessel in thecanal.

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] CONDERON SPEED CANALS.ON 163 Then v=x+y, X and, as the free water-way is equaln - to 1, y = -- n - 1’ therefore v=x+- X 12- 1 (1) Let, for example, 12 = 4. Then v=x+3,X and x=2v. It results, however, from the experilncnts of Darcy and Bazin, as well as from theory, that not only must the area of the channel be regarded, but also its form, and the special nature of the wetted surface. Of all forms of channel, according to this authority, the semi-circular is that which offers least resistance to the flowof water ; as it is also that of which the hydraulic radius is the largest, in proportion to the area. Butthe hydraulic radius, or the areadivided by thewet n perimeter, = is approximately the same for a semi-circle and G,- 2 for a semi-ellipse of equal area. It will be at once admitted that, if an ellipse be taken of which the axes are, forexample, as 6 to 1, it would be rash to assume that the flow of water would be the samethrough two equal semi-elliptical sections, on0 withthe minor axis vertical, and the other with it horizontal. The peri- phery ineach case would be exactlythe same, and thus theordinary formula, as dependent on the hydraulic radius, would be the same, and the volume and weight of water would be the same. But the hydrostatic pressure on the periphery, and therefore the frictional resistance, would be very different. Here,then, is a case where present forlnulas are inadequate fully to investigate the question of speed. For convenience of navigation, the top width of a canal may be generally taken as from 7 to 10 times its depth; and, with the reserve just mentioned, the formula of the hydraulic radius maybe applied to a semi-elliptical section of this proportion as if it were a semi-circle. With this allowance, the formulaabove given, correctedfor any difference of thehydraulic radius, as below exemplified, may be applied to those few facts which are attain- able in the absence of further experiment. The Suez Canal (Fig. 1) has a depth of 26 feet; a bottom width of 72 feet; sides sloping at 2 or 2& to l to within 5 feet of the water-line, and a top width of 326 feet. Thus, with the exception M 2 Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 164 COXDER ON SPEED ON CANALS. [Minutes of of one ortwo portions of the course, thereare flat shallow shoulders on each side of the naviiable channel, which is only

FIG. 1.

112 feet wide at a depth of 16 feet. The area of the cross-section thus formed is 3,862 square feet, and the hydraulic radius is12.34 feet at best, and in some parts of the canal notmore than 10.12 feet. A semi-elliptical section (Fig. a), 163 feetwide at top, ancl 30 feet deep in the centre, would have an equal sectional area of

EIG. 2.

D=30fd SECTIONSOF CANAL,AS PROPOSED BY TIIE AUTHOR,OF EQUAL SECTIONALARE TO THE ACTUAL AmTHE I’ROI’OSED SUEZCASAL.

3,862 squarefeet, and a hydraulic radius of 21 * 31 feet. Thus, according to the usualestimate of the value of thehydrauli@ FIG. 3. FIG. 4.

R-56 fd

SEJII-CIRCULAR SECTION OF EQUALARE.4 TOSEMI-ELLIPTICAL SECTION, WITIS FIGS.1 AND 2. THE SAME AXES AS FIa. 2, BUT DISPOSED VEITICALLY.

radiue, whatever be the resistance due to the back-current caused hy the movement of a vessel in the canal (as determined by the formula V = X + y), it will be increased, owing to the resistance

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] CONDER ON SPEED ON CANALS. 165 tohhat currentdue to the badform of the trapezoidalsection, as measured by the hydraulic radius. This, as before observed, is treatingthe semi-ellipseas equivalent toa semi-circle. A com- parison of the two sections will show, that the fair-way afforded for vessels of 20-feet draught by the semi-elliptical section would be equal to that obtained by widening the existing trapezoidal section by 28 feet. But the present inquiry is as to retardation due to section. In 1870,l the “Warrior” steamed through the Suez Canal in twelve hours and fi€ty minutes, being at the rate of 6 85 knots per hour. Thevessel of that name in the Royal Navy is 380 feet long; and, with an immersed midship section of 1,219 superficial feet, and an indicated HP. of 5,469, is credited with a speed of 14.386 knots at sea. The application of the previously given for- mula (1) will be as follows :- A = 3,862 square feet. U = 1,219 ,, n = 3.16. V = 14,356 knots per hour. X y=-- - 4.544 knots per hour. 2.16 X = 9.812 knots per hour. The back-currenty has thus avelocity of 7 * 68 feet per second. As the hydraulic radiusof the canal is only about one-half that of the best form of channel for an equalcross-section, the resistance clue to this speed (58 98) has to be doubled, and the square root of the product abstracted. This gives a retardatory current of 10.86 feet per second, or 6 -429 knots per hour, and reduces the value of X to 7.927 knotsper hour. The speed actually pra. 5. maintainedwas only 6 83 knotsper hour, and T :l the amount of directretardation due to the section of the canal might accountfor the differ- ence. But the state of the canal in 1870 was - -! -/r such as to reduce themaximum speed in several parts of the course, although a higherspeed is /A attained through the lagoons. In point of fact 6;) the speed obtained has generally been regulated rather by regard to the damage caused to the DIAGRAMILLUSTRAT- banksbythewave produced bythe steamer THE OF RETARDATION. than by other considerations. On application to the Admiralty to ascertain whether the ship

Bulletin dicadaire, No. 22.

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 166 CONDERON SPEED ON CANALS. [Minutes of in questionwas really H.M.S. Warrior,” it proved that it was not. In 1874, according to a ParliamentaryReturn (C. 1392, 1876,p. SS), a Britishship called “Warrior,” of 797 tons net tonnage,was re-measured bythe Suez Canal Company. The area of cross-section of a vessel of this size will be only about one- fifteenth part of that of the canal. The retardation fromback waterwill therefore be only one-fourteenth part of the speed, and the smaller vessel, with proportionately much smaller horse- power, will beat the larger ina restricted channel. In the , according to a statement lately pubIished by Sir Arthur Cotton, R.E.,l the sectional area of the canal is three times that of the boats. A speed of 7 miles per hour in the open river is reduced to 5 miles per hour in the canal. According tothe formula (1) (takingareas alone, without cor- rection for the hydraulic radius), a speed of 74 miles per hour in open water wouldbe reduced to 7miles perhour where the channel has an area between ten and twelve times that of the boat, and to 5 miles an hour where the areas are as 3 to 1. On the River Lee, according to the lateMr. Beardmore, M. Inst. with a boat having a cross-section of 50 square feet, anincrease of section from 165 to 209 square feet was attended by an increase of speed of Q mile per hour. It is not, however, stated on what speed the increasewas obtained. At a rate ofmotion equal to 10 miles per hour in open water, the difference of velocity due to the difference of areaswould be 0 6 mileper hour, and there wouldbe a slight further gain due to the improvement of the hydraulic radius.These examples, deficient as they are in pre- cision, mayperhaps be taken as evidence thatthe effects of retardation due to restrictionof area, and to bad forms of channel, are by no means exaggerated by the formula above suggested. The effect of rough sides, projectingjetties, and the growth of weeds, either at the side or at the bottom of the canal, as also that of mud in suspension in the water, have further to be taken into account as increasingretardation. Coefficients of someof these conditions are given in standard works on hydraulics. The effect of all such obstructions must be to retard the flow of the back-current along the sides or the bottom of the canal. But as the back-current, as a whole, is a function of the speed of the boat, this retardation of a part of it must be accompanied by a corre- sponding increase of speed in the partof the current furthestfrom

Internal Transit, p. 8. Minutes of Proceedings Inst. C.E., vol. xxvi., p. 39.

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the obstacles, that is to say, against the sides of the boat. It is thus evident why the foul state of a canal or river exercises that directlyretarding influence onspeed of transitwhich persona familiar with canal navigation know to be produced under such circumstances. There is one importantpoint as to which direct experiment appears to be necessary before it can be attempted to formulate a complete theory of retardation in canals; that is, the respective influence of width and of depth on speed. As to this, the data at presentavailable have somewhat anomalous results. Thus, on anIndian canal, 60 feet wide, an officerof the Madras Public Worksdepartment informed the Author thatas the depth of a longreach increased from 6 to 12 feet, the speed of a light steamerincreased from 5 to 10 milesper hour. And the extra- ordinary starts, mentioned by several of the speakers in thedebate above cited, made by boats on passing into deeper water, seem to be more rapid than is explicable by mere difference of area. It mayprobably be found that these apparent anomalies are referable in part to the relation between the form of the vessel and of the wave that it produces, and that of the canal. Thus, on the Indian canals, where the boats have a draught of from 15 to 21 inches, and a horizontal entrance, being in some cases propelled by a singlepaddle-wheel at the stern, the displacement of the water is effected downwards, and the slightest variation of depth is instantly felt. In other cases, especially in river-navigation, where the entrance is vertical, and throws a wave to either side of the channel, it is possible that the effect of a change in width may be more directly felt than that of a change in depth. As to this, although a simple formula may be suggested, direct experi- ment is highly desirable. Where the cross-section of a canal is very small in proportion to that of the craft navigating it, the advantage to be obtained by enlargement is mostconspicuous. Thus,for the same boat, in passing from a canal where A = 2 a into one where A = 3 a,, there will be an increase of 33 per cent. in speed in the latter as com- pared with the former. Suppose the same speed to be maintained in the two cases, the cost of traction will be nearly as 8 to 5. Considerations of this nature are of the highest importance, as determining the section that should be given to any new canal. In the case of a ship-canal,which is the class of enterprise on which much public attention is now concentrated, it appears from the preceding investigation that a gain of 1.8 knot per hour may be attainable by the adoption of a scientific section, without any

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 168 CONDER ON SPEED ON CANALS. [Minutes of increase in the quantity of excavation. This is equal to a gain of from 17 to 18 per cent. in time ; or, if the same speed be main- tained, to about 21 *5per cent. in cost of traction. The speed maintained on inland water-ways is kzpt down by (l)the changes of level ; (2) the increase of resistance, which is as the square of the velocity; and (3) the fear of eroding the banks. Fig. 6 shows the rat.io of increase of resistance to increase of velocity in open water. Humanlabour is still employed fortowage on some of the Dutch, Belgian, and German canals. Boats of from l5 to 26 tons are towed by men at a speed of 1to 14. mile per hour. Dr. Meitzen, a German authority, allows a duty of 11 miles a day, including all stoppages. Steam tugboats on the Belgian canals are restricted ,to a speed of 2; miles per hour, and on the wider rivers to 43 miles per hour. On the canal joining the Tiege to the Vistula, steam-tugs draw trains of barges 410 feet long,the speed being restricted to 3 miles perhour. The steam-tugs putby Mr. Beardmore on theriver Lee towed from 50 to 60 tons, at from 2 to 24 miles per hour, in the Cuts, 3 to 33 miles per hour in the larger sections, and 5 miles per hour in the Thames. On the the speed of a steamer towing one vessel is put at from 3 to 34 miles per hour. On the Rotterdam Canal four boats, of 130 tons each, are towed by ascrew steamer, which also carriescargo, at 5 miles per hour. In Sweden, as well as in Holland, where the channels are narrow, the usual speed is 33 miles per hour, but 5 miles an hour is generally attained, the difference depending on the area of cross-section. In curves and shallows, in narrow canals or .rivers, a breaking wavefirst appears at from 3 to 33 milesper hour. At 4 miles an hour the effect of the wave on the banks becomes injurious. At 5 miles an hour the waveincreases, breaking over the towing- path, and being followed by other waves in succession. In parts of the Clyde from 120 to 150 feet wide, and about 10 feet deep, vessels of from 120 to 150 feetlong, with from 16 to 18 feet beam, and from 5 to G feet draught, are propelled by engines of from 80 HP. to 100 HP., at a speed of from 8 to 9 miles per hour. At this speed a surge rises at from 2 to 3 miles ahead, and a wave is caused which measures 8 or 9 feet from the crest to the bottom of the trough. A head of this huight gives a theoretic speed of 16 miles an hour, which shows a loss of 50 per cent. dueto restriction of channel. speed of 5 knots per hour, or 8 ~37feet per second,corre-

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sponding to a head of 1* 08 foot of water, is the limit of speed fixed for the SuezCanal. Thismay perhaps be takenas the normal speed to besought on the canals of . On the determination of the normal speed, and of the tonnage of the boats to be accommodated, will depend not only the steam-power required, but the section of the canals and the dimensions of the locks. A speed of about 30 milesa day, including stoppages, is even now attainable on English canals.

FIG.6. 100

10

CURVEOF REKISTANCEDIBECTLY AB SPEED.

The loss of time due to locks is more serious on many English, than on mostcontinental, canals, although there are canals in Belgium withfar more numerouslocks thanthe average in England. A rise of 8 feet is overcome on some canals in three and a half minutes. On the Aire and CalderNavigation, Mr. Bartholomew, M. Inst. C.E., has attained a rise of 7 feet 6 inches in two and a half minutes, and a rise of 13 feet 6 inches in three and a half minutes. These figures give the rates at 2 3, 3, and 3 *8 feet per

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 170 CONDERON SPEED ON CANALS. [Minutes of minute,either forascending or fordescending, a speed which may probably be increased by better construction of locks. By theuse of lifts or of inclined planes, where a rise can becon- centrated, much greater speed than the above may be attained. A height of 51 feet is cleared by the Anderton lift in eight minutes. On theMorris canal incline a height of 51 feet is overcome in three and a half minutes; and on the Blackhill incline, on the Forth and Clyde Canal, a height of 96 feet is overcome in ten minutes. The corresponding speeds are 6.37 feet, 14.5 feet, and 9 * 6 feet per minute, or about three times thespeed now attained by locks. Theheights to be overcome in crossing England from the Thames to the Severn are,358 feet on the 204 miles of the Wilts and Berks route, 474 feet on the 180 miles of the Kennet and

FIG.?’.

0 I0 12?I,t,I,,,00 40 50 60

MILES PER HOUR DIAGRAKILLUSTRATING THE RELATIONOF SPEEDAND COSTOB RAILWAYS.

Avonroute, and 392 feet on the 206 miles of the Thamesand SevernCanal route. This gives anaverage change of level, counting ascent anddescent, of 4.14 feet per mile, or a little more than one-fourth of the ruling gradient laid down by Mr. Itobert Stephenson for the and railway. From the Report of the Select Committee on Canals, p. 125, it appears that on 2,440 miles of canal there exist one thousand nine hundred and one locks, or a to every 1 37 mile. This givesan average rise or fall for the system, as far as it is represented by the times returned, of 5.84 feet per mile. At the rate of 3 feet per minute, thesefigures show a retardation of from 1 to 1 75 minuteper mile over the Thames and Severn lines of junction, and of 1 95 minute per mile as the general average. Taking the more uneven section, a running speed of 5 knots,

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or 5.76 statute miles per hour, on an ordinary English canal, will be reduced by the delays caused by the locks to a speed of 4.9 milesper hour; allowing of the performance of adistance of 58.8 miles in twelve hours, or nearly double the speed of prompt canal service at present. This is about one-third of the running speed of the mineral trainson the railways of the United Eingdom. But a terminus to terminus speed of 5 miles an houris as much as is sometimes attained by the mineral trains ; and it is in evidence

FIG. 8. 101

CURVEOF RETARDATIONINVERSELY ~6 DWH. that the deliveries of despatches made by river and canal from to Birmingham are as prompt as thosemade by railway between those two important towns. The cost of speed on railways may be ascertained by analysing the expenditure, and arranging it under the heads of costs in- dependent of velocity, costs increasingwith velocity, and costs decreasingas velocity increases. Fig. 7 isagraphic repre- sentation of suchan analysis of the workingexpenditure of therailways of the UnitedKingdom inthe year 1878. The

Downloaded by [ University of Liverpool] on [15/09/16]. Copyright © ICE Publishing, all rights reserved. 172 CONDER OX SPEED ON CANALS. Plinutes of materials for a corresponding diagram of canal cost and speed are not at present fully accessible ; and, as the question of relative areas has to be considered at the same time, not one, but a series of diagrams would be requisite for full illustration. Fig. S shows, approximately, the decrease of resistance due to the increase of depth, on the principle shown in Fig. 5.

The object of the Author in the foregoing Paper has been, first, to call the attention of the profession, and of those who consult its members, to the character of the experiments which are requisite for the determination of the true theory of loss of speed in canals; and, secondly, to propose an hypothesis, illustrated by such facts as are at present on record, according to which future observations may be so grouped as to Iead to the ultimate determination of the true theory.

The Paper isaccompanied by several diagrams, from which the woodcuts in the text havebeen prepared.

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APPENDIX.

-

TABLE CHRONOLOGY of NAVIGATION-and CANAL-LEGISLATIONin ESGLAND.

XVth Century. 714. navigation. 715. River Kennet ,, 1423. navigation. 716. RiverWear ,, 1425. River Lee 720. and Liverpool canal. 1462. River Ouse (Yorkshire) uaviga- 720. Rivers Mersey and Irwell navi- tion. gation (and 1794). 720. navigation. XVIthCentury. 720. RiverDane 71

1503. navigation. .721. RiverEden 1, 1504. River Stour () navigation. ,726. DunRiver 7 1531. Rivers and Ouse navi- -726. BeverleyBeck ,, gation. -730. Stroudwater Canal ,, 1531. River Exe navigation. -737. RiverRoden 99 1570. RiverLee ,, .737. Duke of Bridgewater'sCanal, 1571. Welland ,, (and 1759). 1572. Exeter Canal. 1749. Rivers Ley and Lunenavigation. 1751.Narr River 9, XVIIth Century. 1751. RiverAvon ( 1 1623. River navigation. 1753. navigation. 1662. RiverItchin ,, 1755. Sanlrey canal ,, 1662. RiverWye ,, 1757. RiverBlyth ,, 1664. RiverAvon :, 1757. RiverIvel 7 1664. RiverMedway ,, (upper) 1758. Rivers Calder and Hebble navi- 1670. RiverWey ,, gation. 1670. Rivers Bure, Yare, andWave- 1759. navigation. ney navigation. 1759. navigation. 1670. River Ouse (Suffolk) navigation. 1763. Louth 99 1670. 9, 1766. ,, 1672.\!'itham River 23 1766. . 1678. Rivers Paland Vale ,, 1766. and 1699. Rivers Tone and Parret ,, Canal. 1699. Rivers Aire and Calder ,, 1766. Rirers Chelmer and Blackwater 1699.Trent River , navigation (and 1793). 1767. RiverUre navigation.

XPIIIth CentuTy. 1767. 99 1700. Rivers Avon and Frome naviga- 1767. RiverAncholme ,, tion. 1768. . 1700. River Dee navigation(and 1732.) 1768. canal. 1700. RiverLark ,, 1768. Birmingham Canal. 1701. River Derwent ,, 1768. Forth and Clyde Canal. 1702. River Frant ,, 1769. Oxford Cad. 1705. River Stour ,, 1770. .

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1770. Leeds and Liverpool Canal. 1793. Caister Canal. 1771. . 1793. Canal. 1771. . 1793. Canal. 1772. . 1793. . 1772. Canal. 1793. . 1773. River Bnre navigation. 1794. Montgomeryshire Canal. 1774. Sir John Ramsden's Canal. 1794. and Napton Canal. 1771. Canal and Haven. 1794. Canal. 1775. Gresley Canal. 1794. Canal. 1776. . 1794. Huddersfield Canal. li76. Canal. 1791. . 1758. . 1794. Mersey and Irwell navigation. 1778. Bedford River. 1794. Canal. 1783. . 1794. Canal. 1785. River Arnn navigation. 1794. Somersetshire Canal. 1788. Union Canals. 1791. Ashby-de-la-Zouch Canal. 1789. . 1794. navigation. 1789. Canal. 1795. Wilts and Berks Canal. 1790. River Ouse (Yorkshire) naviga- 1795. Ilchesttr and Langport naviga- tion. tion. 1790. . 1795. Newcastle-under-Line Canal. 1791. Hereford andGloucester Canal. 1795. Canal. 1791. Leicester navigation. 1796. Dorset and Canal. 1791. Wreak and Eye Rivernavigation. 1796. . 1791., , and Bury 1796. Aberdeen, or Donand Dee Canal. Canal. 1796. navigation. 1791. Canal. 1796. Salisburyand Southampton 1791. Canal. Canal. 1791. Neath Canal. 1791.Worcester andBirmingham XIXth Cenlury. Canal. 1800. Thames and Canal. 1792.River illedwwgr (lower)naviga- 1801. Grand Canal. tion. 1801. . 1792. . 1802. River Exe navigation. 1792. Canal. 1803. Glenkennie Canal. 1792. Canal. 1803. T'avistock Canal. 1792. . 1803. . 1793. Gloucester and Berkeley Canal. 1803. Thames and Sevcrn Canal. 1793. Canal. 1805. navigation. 1793. and Abergavenny Canal. 1805. Ashton and Canal. 1793. Stratford-on-Avon Canal. 1806. Glasgow and Paisley Canal. 1793. Leicestershire and Northampton- 1807. River Adur navigation. shire Canal. 1807. 1793. Canal. 1807. . 1793. Grand Junction Canal. 1808. Rivcr Tces navigation. 2793. River Foss navigation. 1810. Gnnd . 1793. . 1811. Bridgwater and Taunton Canal. 1793. Stainforth and Keadby Canal. 1812. London and Canal. 1793. Ulverstone Canal. 1812. Regent's Canal. 1793. Canal. 1813. Bure and Dillon Canal. 1793. Warwick and Birmingham Canal. 1813. Wey and Arm Canal

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181 5. Canal. 1826. Canal. 1816. Canal. 1826. BirminghamandLiverpool 1817. and Arundel Canal. Canal. 1817. and Glasgow Canal. 1827. and Lowestoft naviga- 1819. Canal. tion. 1819. Bude and Launcester Canal. 1S2S. Avon and Canal. 1820. . 1828. Nene and Wisbeach Canal. 1824. Kensington Canal. 1829. . 1824. Union Canal. 1830. Ellesmere and Canal. 1825. Englishand Channels 1812. River Severn navigation. Canal. (Liskeard and Love.) 1852. Droitwich Junction Canal. 1826. Alford Canal.

TABLEII.-DIBIENSI~NS of CANAL-LOCKS.

Size of Locks. Date. Name of Undertaking. Length. 1 Width......

Feet , Inch(?8 ' Feet. Inches. 1792 AberdareCanal ...... 7010 10 9 1C99 Aire and Caldernavigation, old ... 72 0 ~ 18 0 , new ... 212 0 22 0 l767 Ancholme navigation ...... 70 0 ~.Ifi 0 1792 ...... S3 0 89 1778 Basingstoke Canal ...... 72 0 14 0 1773 Beck ...... 71 0 18 1 1768 Birmingham Canal ...... so 0 80 1759 Bridgwater Canal ...... 84 0 l 15 0 1811 Bridgwater and Taunton Canal ... GO 0 ' 13 9 1819 BudeHarbour and Canal . . ... 63 0 j 14 7 1771 Chesterfield Canal ...... 70 10 1 104 6 1768 ...... 72 0 76 l795 DerbyCanal ...... 1 90 0 14 6 1707 Dermentnavigation ...... 45 0 15 0 1768 Droitwich Caual ...... 81 6 14 C 1670 Foss-Dyke navigation ...... 82 0 17 3 1790 Glamorganshire Canal ... 67 0 10 6 1792 Gloucester and BerkeleyCaial ' ... 165 0 37 0 ,, .. 108 0 24 0 1793 GrandJunction Canal ...... 87 G 15 0 181 0 GrandUnion Canal ...... 78 0 72 1793 GranthamCanal ...... 91 0 15 0 1790 Herefordshire and Gloucestershire Canal . 72 0 80 1715 KennetRiver navigation ..... 80 0 14 0 l794 Kennett and Avon Canal navigation .. 75 0 14 C 1712 Avon Rivernavigation ...... 108 0 18 C 1570 Lee River ...... 96 0 13 0 1770 Leeds and Liverpool Canal ..... 70 0 16 0 1791 Leicester navigation ...... 70 0 14 6 1793 Leicestershire and NorthamptonshireCanal 88 0 15 6 1801 Leven Canal ...... L 72 0 17 0 1763 ...... 87 6 15 5

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TABLE11 (COntinzled).-D~ENSIONS Of CANAL LOCKS.

Size of Locks . Date. Name of Undertaking. Length . Width . .. Feet. Inches Feet . Inches . 1826 1 MacclesfieldCanal ...... 82 0 73 1792Medway (Lower). navigation ... 86 0 23 0 1664 (Upper) ...... ‘‘ Var ble.” 1 791 Meiion1791 1 Mombray ...... 91 0 150 1794Mersey andIrwell ...... 82 0 15G ..... 68 G 100 Newport Pagnell Canal ..... 660 150 ...... 91 0 15 0 ..... 70 0 22 G ...... 70 0 70 1794 . PeakForest Canal ...... 81 0 80 1815 ~ PocklingtonCanal ...... 60 G 150 1812 . liegentsCanal ...... 90 0 152 1842 SevernRiver ...... 100 0 200 . 80 0 1772 ..... 76

1792 ~ Sleafordnavigation ...... 90 0 150 1794 SomersetshireCoal Canal .... 70 0 80 - 1793 Dearne and Dove Canal .... 57 0 1411 1725 Dun Rivernavigation .. 61 6 15 3 1793 Stainforthand Keadby Canai . . 68 0 17 6 1815 Sheffield Canal ...... 61 G 153 1765 Stafb-dshire and Worcestershire Canal 75 0 70 1792 . StortRiver navigation ..... 100 0 13G 1776 i Stourbridge ...... 71 0 70 1790 Gtowmarket ...... 76 0 146 1793 Stratford-on-Avon Canal ..... 79 0 78 1793 Surrey Commercial Dock ..... 119 0 200 1803 TavistockCanal ...... 74 0 80 1782 Thames and Severn Canal .....l 70 0 13 0 1811 ToneRiver navigation ...... 55 0 140 1699 TrentRiver ...... 90 0 150 1766 Trent and Mersey Canal ...... 80 0 90 l793 UlverstonCanal ...... 72 0 80 1767 Ure River ...... 60 6 166 1793 Warwick and Birmingham Canal ... 72 0 70 1794 Warwick and Napton Canal .... 73 0 72 1795 Wilts and Berks Canal ...... 78 0 80 1794 WisbechCanal ...... 54 0 140 1670 Witham navigation ...... 74 4 173 1751 Worcester and Birmingham Canal ... 80 0 76 1791 .. LowerAvonnavigation . 79 9 16 8 .

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TABLEIIL-SPEED ATTAINED on CAXALS.

~ - - Miles per Miles per Hour. Day. - ~.______~__~ _~__- On Belgiau canals, human labour ...... l to 1: ,, German ,, .. ,, ...... 11 ,, English ,, horse towage(including 71 locks in 51 miles) ...... 27 .. Belgiancanals, steam towage ... 2; ,, German ,, ...... l 3 River Lee,, River ,> ...... 2 to 33 River Thames,, River ...... , 5 ,, Grand Junction Canal ,, ...... , 3 to 33 ,, River Meuse ...... ' 43 ,, RotterdamCanal ,, ...... 5 .. Swedish canals andrivers ...... 34 to 5 Breaking wave in shallow Been at ...... 3 to 38 ,I ,, becomes injurious at ..... 4' Snccessive waves appear at ...... 5 Surf 4 feet 6 inches high on Clyde rises at .... 8 to 9 Limiting speed on Suez Canal ...... 5.76 Loss of speed due to trapezoidal form of section on)! 0.55 SuezCanal ...... '

TABLEIV.-Loss of TIMEDUE to RISEor FALL.

- i Per Foot. \Feet per mile.

Xinute. Rerks and Wilts Canallocks .. 0.434 ,-lire and Calder navigation . .. 0.333 9, 9, ...... 0.264 Anderton Lifts ...... 0.157 Morris CanalIncline ...... 0.069 Forth and Clyde Canal Incline ...... 0.104

Average rise per mile on returned number of locks- viz. 1 to 1.37 mile ...... f' .. 5.84 Average rise or fall per mile from Thames to Severn . .. 4.14 Minute per mile. Average retardation due to locks on English canals . 1.75 to 1.95

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