THE REGISTER OF PENNSYLVANIA. DEVOTED TO THE PRESERVATION OF EVERY KIND OF USEFUL INFORMATION RESPECTING THE STATE. EDITED BY SAMUEL HAZARD, NO. 51, FILBERT STREET. VOL. II.-NO. 1. PHILADELPHIA, JULY 19, 1828. CANAL DOCUMENTS. To the Board of Canal Commissioners of the State of NO. 29. back to the vicinity of the dividing ridge and brought down a new line through the bottoms of the valley had time permitted:-As the case was, I went back about Agreeably to instructions, communicated by the Se- six miles on my line and made an offset, contenting my cretary of the Board, in June last, I repaired to the west-self with connecting this work with that at the head of ern part of the state, immediately after the general ex- the valley by a line carefully run with the compass. amination of the military academy, for the purpose of reconnoitering and surveying (as far as time would permit) the routes of the N. W. section of the Pennsylvania canal, from the waters of French creek to the bay of Presque Isle. The first of those routes to which my attention was directed, was that by the way of Conneaut Lake and the Valley of the Big Conneaut, upon which, having how completed the necessary plans and calculations, I have the honour of submitting the following report. Upon examining the ground in the vicinity of the Forks of the Big Conneaut, and forward as far as Elk creek with the view of adjusting the level and direction of the new line, it was found, with few exceptions, unexpectedly favourable. A bench of smooth uniform ground presenting itself on nearly five miles of the direct route toward Elk creek, and at a sufficiently low level to admit of shunning the chief difficulties of the Conneaut valley. In this direction, therefore, the line was brought by the sources of Crooked creek to the valley of Hall's run, and so, by a rapid descent, into the The operations of the survey commenced, of course, at Conneaut Lake, and had, for their first object, the de-bottom of that valley and the great valley of Elk creek. termination of the various questions connected with the summit level. The crossing of this stream having generally been considered as one of the principal difficulties on this route, it became necessary to explore it with particular care. Several days were accordingly employed in examining the character of the valley, and in levelling and measuring at the different points selected as crossing places.Every thing being at length ascertained, upon which the comparison of these crossings could at all depend, the experimental line was continued across the creek, and down the eastern side of the valley of the village of Fairview. At this point the ground was explored with a view of reaching, by the most direct and convenient route, a level bench of land which ranges with great uniformity towards Erie, along the north side of, and a little below the Ridge road. Having satisfied myself on this point, the operations of the surveys were continued, without further hindrance, to the banks of Walnut creek. Reverting to the report of last year, on the subject of the French creek feeder, it will be recollected that the dividing ridge between the waters of Conneaut Lake and those of Lake Erie pass at a moderate elevation within a few miles north of the former, and that among the various routes for crossing it, that by the east hranch of Beaver Dam run is designated as the most favourable. Having fully satisfied myself on this point, on the former occasion, it only remained, with reference to this point of the route, to examine the ground a little more in detail. The experimental line, for this and other purposes of the survey, was commenced at the surface of the Conneaut Lake, near the mouth of Beaver Dam run, and carried on the eastern side, generally as near it as was consistent with the accuracy of the level, to the height of land near Grier's Improvement, on the road west of Brightstown. Crossing the ridge at this point, The crossing of Walnut creck is another of the diffiand taking advantage of one of the tributaries of the culties of this route, but of a very different character Big Conneaut, the line was restored almost immediately from the one first mentioned. It presents, indeed, a to the level with which it commenced, at the surface of wide and deep chasm with very precipitous banks, Conneaut Lake. This brief operation being sufficient, which evidently cannot be passed without an expensive in addition to the work of last year, for determining the construction; but the face of the adjacent country is route and mode of construction on the summit level, the perfectly regular, and the level well preserved to the line was continued, without delay, down the Valley of edge of the precipice on both sides; so that the crossing, the Big Conneaut. From the impression I had received so far as regards the adjustment of the route and the plan of the character of this valley, and the nature of the of construction, is reduced to a very simple case. Only ground in a direction towards Erie, I was led to believe a few hours were required to complete the examinathat very important advantages would be gained, in tions at this place, and transfer the level to the cast side point of distance and facilities of construction, by keep- of the creek, after which the line was resumed and coning the level as long as possible at the full elevation of tinued upon the same bench, and at the same average the summit level, and the survey was conducted ac-level as before. Every thing proved remarkably facordingly, along the eastern slope of the valley. At vorable on the residue of the distance to Erie, and it onfirst, for a considerable distance on the line thus explor-ly remained to explore the ground in that vicinity, for ed, the features of the ground harmonized very well the lockage down to the surface of the lake. This was with this plan; but, as the line gradually gained upon | accomplished, on the 18th of August, and with it the the surface of the slope, the difficulties greatly increas-field duties of the party on this route were considered ed; and, at length, when the party had proceeded as far at an end, having occupied exactly five weeks from the as the east Branch of Big Conneaut, it became quite time of their commencement at Conneaut Lake. evident that the impediments already encountered, to- Having thus given a view of the operations of the gether with those fairly to be calculated upon in pro-survey, I proceed to notice, more particularly, the chaceeding, would more than outweigh any advantages that racter of the route and the nature of the various concould possibly be derived from the choice of this route. structions connected therewith. In coming to this conclusion, and abandoning the line which had been so far advanced, I should have gone Section 1.-The Summit Level. evidently embrace the connexion of the summit level with the routes down the southern slope; but, as those are made the subject of separate surveys, not yet reported upon, I can only at present consider the route under discussion in its relation to the French creek feeder. The feeder, it will be recollected, was considered in my last year's report as terminating in the vicinity of the outlet bridge near Cummings' tavern, and at the level of eight feet above the habitual surface of Conneaut Lake:-At that point, therefore, (marked A. in the accompanying maps.) I take the commencement of the present line. An easy inflection carries it across the tongue of land on the west side of the outlet, and through a small portion of the lake to the western shore; it then skirts along the firm bank of that shore, and, in a very even course, by means of a few trifling excavations and embankments, until it passes Wolf Point, after which it changes slightly to the left, as the ground suits, and passing directly up the Beaver Dam swamp, falls into the course of the run a little south of Lewis' Hill. Near this point, (marked B. in the maps,) the deep cutting commences; the line in the mean time passes by the bed of the stream, round the west side of the hill, and thence in a direct course through the swamp, to the bench-mark, (at station No. 49,) on the dividing ridge. About 100 yards beyond this, continuing the same direction, it strikes a head water of the Big Conneaut in the general course of which it descends, to the station No. 55, marked C.) where the cutting again runs out at the surface of the ground. line entirely independent of the lake. Upon supposi tion therefore, I have made my estimate. The length of this section from the guard gate near Cummins' is 5 miles and 213 perches, 695 moderate embankment and the remainder excavation, generally moderate, and only 22 feet entire depth on the dividing ridge. Second Section, down the valley of the Big Conneaut. In detailing the field operations of the survey, I have already given some idea of two widely different modes, by which the canal may be conducted down this valley. First by keeping the level of the summit along the face of the eastern slope, and secondly, locking down through the bottom of the intervale. The first of these was the plan upon which I commenced under the expectation of being able to shape my course more directly towards Erie, and of obtaining more convenient crossing places for the much dreaded valleys of Elk and Walnut creeks, the particular circumstances which induced me to abandon it in favor of a route down the bottom of the valley. I have now to remark, with respect to the valley itself, its lateral slopes were found remarkably intersected by ravines and gullies, produced in some instances by permanent streams, and in others, by the occasional wash of the country. These generally proceed from small beginnings at the distance of a mile or two from the margin and run out again to terminations equally small in the valley, but in the intermediate distance, and particularly at the verge of the slope, they have frequently the most extraordinary dimensions. The difficulty of running a level line over ground of this character is enhanced by the general pitch of the ground, valley and upland, towards the lake. For it generally happens in consequence of this, that a level taken over from the bottoms near the head of the valley cannot fail of encountering all the gullies, and as it rises on the face of the slope it must encounter them with greater and greater dimensions, until it finally crosses them at the very maximum of their breadth and depth. This was the case in the line actually run. In the course of ten or twelve miles from the summit, I had already experienc ed a remarkable increase both in the number and magnitude of the gullies, and by the time I arrived at the Eric county line, I had passed without counting those of smaller dimensions, no less than twenty which might be considered as extraordinary, some, often being from 100 to 200 yards in width and 50 or 60 feet deep. So far as the Conneaut valley was concerned therefore, there remained at this stage of the survey not the smallest doubt of the superior advantage of a line locked down thro' the bottoms. But I still indulged the expectation of se curing great advantages in the length and direction of the route to Erie by keeping the high line, and it was not until I had passed the Erie branch of the Big Conneaut that the hopelessness of this route in all respects became fully manifest. I had then before me a district of very broken and irregular country, deeply intersected by the tributaries of Elk creek, on the left a system of parallel ridges, which a little further on, assume a distinct and regular character, and intercepted all approach to the lake except by deep cuttings or expensive constructions in the bed of some of the streams; and finally, the necessity of diverging considerably to the right of the proper direction in order to retain my Thirdly, the navigation if unprotected on the side of present level if I would gain any advantage by it in the the lake, will be less safe and convenient than an ex- crossing of Elk and Walnut creeks. These and other traordinary canal, and if so protected, the expense of similar considerations, determined me without scruple construction will be decidedly in favor of the latter. to the choice of the lower line. According to this deFourthly, no advantage will be gained, in any event, in termination, the line is located from the point C. through point of expense; for it is found by a careful estimation the first and second bottoms of the valley, in such a of both modes, that by giving proper attention to the manner as to avoid almost entirely the irregularities of eonstruction of the dams, and including those at the the higher ground. Lockage is introduced, as the defoot of the lake, formerly estimated, the plan of raising clivity requires it, and at such particular points as shall the lake will cost from 500 to 1000 dollars more than the best preserve the directness of the line, and its proper construction of a separate canal. Should the locating location in other respects. For the purpose of shortenengineer, with the results of the southern surveys being it as much as possible, the upper part of the route fore him, agree with me in these opinions, he will cross is taken on the west side of the creek, and transferred the outlet by a culvert at Cummins', and make the whole as the latter increases in westing. The crossing place The construction on this line consists, for the most part, of mere excavation and embankment, and requires no particular remark, except as regards its connexion with Conneaut Lake. In the provisional examination of this summit, it is well detailed in the former report. The only view taken of this connexion, in the event of the canal passing on the west side of the lake, was by daming the latter to the eight feet level, and merely constructing a towing path along the western side. This was believed to be the most natural construction, and as converting the lake into a reservoir, to afford some security against the possible failure of a supply from French creek. The examinations of the present year, however, have shown so considerable a supply of water, from the springs and brooks of the northern slope, as to render this plan entirely unnecessary as a measure of precaution, while they afford also some reason to doubt its feasibility in other respects, in comparison with a separate construction. There are nearly 600 perches of the route above described which it appears will require embankment, from four to ten feet entire height. Now, in the first place, a simple embankment of this extent, exposed to the action and agitations of the lake, will be far more liable to accident than a canal embanked in the ordinary way and the consequences of a breach, besides that it will produce a much longer intermission to the navigation, will be more disastrous in every respect. 2dly. This mode of construction will cover a large extent of low ground at the head of the lake, with a thin sheet of stagnant water, the effects of which can hardly fail of being injurious to the health of the vicinity, and will also produce a considerable increase in the assessment of land damages. is perhaps taken rather high in location on the map, but on the ground may be adjusted at any point, as circumstances may determine, above, or in the vicinity of Fors ter's mill. The quantity of lockage which may be admitted in this part of the route depends partly upon the circumstances and character of the valley, and the nature of the ground on the further route towards Elk creek. Upon this principle it is taken at 170 feet which requires a moderate deep cutting on the further route, but avoids all the gullies of any magnitude in the valley except two, neither of which exceeds 70 yards in width by 20 and 26 feet in depth, respectively. This lockage is distributed in fifteen locks of 11 feet 4 inches average lift. One foot 4 being added for the purpose of passing (in an extreme lockage) 44 feet per second, more water than is passed by a ten feet lock, which quantity is re-in a very favorable situation with respect to our route. quired in addition to the supply from the springs and brooks of the northern slope, to compensate the evaporation and leakage on the remainder of the route towards Erie. The increased lift is also desirable on some other accounts, the construction will cost somewhat less; and the time of locking through the entire lift will be less by several minutes than would be required for passing seventeen 10 foot locks. to wind down the east side of the valley until the descent of the country enables us to take the surface and resume our direction towards Erie. We thus gain also, the advantage of passing two parallel ridges of the lake slope, in connexion with the passage of the creek. The examination of the valley was conducted in conformity with this plan. Those places had been suggested as promising some advantages for crossing. First, at Anderson's mill dam, about a half a mile above our routes. The second, at Anderson's crossing place, near the Rich hill; (so called) also a little above our route; and the third, near the mouth of Hall's run, a little below the route. In examining these, a fourth point also attracted some attention, and was examined in comparison with the others, viz. about 400 yards below the Rich hill, and The length of this section from C, to the point D, (in Michael Jackson's meadow) is 163 miles. Its location on the map will probably require some corrections, as it was unavoidably laid down from compass notes only; but in the fine bottoms of such a valley, and with 170 feet of lockage there can be no difficulty in making these corrections in such a manner as to ensure the most direct and favorable route in all respects. Third Section, from the valley of Conneaut to that of Elk Creek. This part of the route as already intimated, takes advantage of a very convenient range of level ground which skirts along the west boundary of Elk creek township, in the precise direction of the shortest route to Elk creek, and was ascertained indeed by an experiment for that purpose, that a lower graduation than the one above mentioned, which would have excluded us from the use of this ground, would have brought us upon the ground of much less favorable character, and with an increase of no less than four miles in the distance to the creek. The only disadvantage accompanying it, but which would prove nearly the same in any location, is the crossing of Jackson's run and the east branch of the Big Conneaut. The former according to our graduation is a gully of 23 feet by 100 yards, and the latter 26 by 176 yards, with a depression of about ten feet more in the bed of the creek. Both, however, are sufficiently well provided with earth for the purpose of embankment. From the east branch, eastward, the ground is of the most favorable character; and the line passing by a slight deep cutting into the head of the valley of Crooked creek locks thrown 314 feet, in three lifts, to a dividing level between that and the valley of Hall's run. Length from Michael Jackson's to the head of the grand lockage in the valley of Hall's run 6 miles and 9 perches. Fourth Section, crossing the valley of Elk creek and the deep cut. This valley has the character of an immense irregular gully, varying in the vicinity of our line, from 4 to 700 yards in width and cutting down through all the benches of the lake slope, to an extreme depth of more than 200 feet below the level at which we approached it. To take in the whole of it, by any mode of crossing whatever, is of course out of the question; the only feasible method is to lock down to into it to such a level as will reduce the crossing to reasonable limits, and then This word is used to express peculiar features in the slopes generally of the country under examination. Those slopes occurring in successive graduations, some thing in the form of ridges, rather than declivities. The level surface of each step is called a bench. The points upon which these crossings were compared, were 1st, their relation to the routes; 2d, the height and depth of embankment necessary, and the supply of earth necessary for constructing it. 3d. The length and height of the acqueduct. And 4th, the facility in each case, of leading the canal by the east bank of the valley. The chief merit of the crossing at Anderson's mill, consists in the height and relation of the immediate bank, being such as to require little or no embankment, and an acqueduct of moderate length. On the other hand, however, its position with respect to the route, is rather an objection; and the difficulty of leading the canal from it by the east side of the valley, a very formidable one. In general, the immediate banks of the creek, on both sides, are precipitous, the stream having worn down its bed through the soil of the intervale, and to a consider, able depth in the soft friable slate which constitutes the substratum. In some places, it has encroached upon the main branch of the valley in such a manner as to form a raw, crumbling precipice of 70 or 80 feet in height, with a steep rising aclivity, frequently 40 or 50 feet higher. One of these precipices, 280 yards long, occurs on the east side of the creek, nearly opposite the Rich Hill, and presents a serious difficulty in the way of any prospect which would require the construction of the canal along its face. No construction of the kind could be considered as safe then, unless supported, at least in part, by a wall of masonry, brought up from the bed of the creek; and this, which under any circumstan ces, would be a work of extraordinary expense, becomes a paramount objection in the present instance, in consequence of the scarcity of stone. This objection applies equally to the crossing at Anderson's mill and that at Anderson's crossing place, both of which require a passage for the canal down the val ley, by the way of this bluff. Considering these, therefore, as excluded, it only remains to institute a comparison between the other two, viz. One, 400 yards be. low the Rich Hill, and the other at the old mill, near the mouth of Hall's run. Both of these are in a conve nient relation to the route, the first being approached by the eastern, and the other by the western side of the valley of Hall's run. The Rich Hill is an insulated knob, situated between Hall's run and Elk creek, about half a mile above the forks. It appears to be the remnant of a tongue of up. land, which at some former period, may have supported the valley of these two streams, and of which, another trace is left, in the form of a low, second bank, which extends down nearly to the hill. By taking advantage of this second bank in connection with the western slope of the hill, a canal may be brought at a convenient elevation, to within about 360 yards of the crossing place, with a very little extra labour. The remaining distance is an intervale bottom, with an average elevation of 34 feet above the bed of the creek. This would, of course, require embankment for any additional elevation; but the immediate vicinity of the hill, affords an abundant supply of earth for this purpose. The trough of the stream at the point of crossing, is 380 feet wide; but of this, 180 feet consists of low bottom, from 6 to 12 feet high, which may, with great convenience, be embanked to any additional height by the earth from a high, and rather steep bank, which overlooks it. In this way the aqueduct may be reduced to as little as 150 feet; which, in a vicinity badly provided with stone, is a point of some consideration. Finally, the line from this crossing place, down the east side of the valley, is attended with litttle or no inconvenience whatever. Such is the crossing by the Rich Hill, that near the old mill is approached as already mentioned, by the western side of the valley of Hall's run. The upland, however, recedes gradually from the line on that side, in such a manner as to render some embankment necessary, for nearly half a mile, before reaching the crossing place. At 550 yards from the latter, the upland fails entirely, and on this distance an embankment would have to be constructed, at an average of at least 8 feet higher than that at the Rich Hill, besides a heavy culvert and extra embankment, at the crossing of Hall's run. The expense of these constructions, would be increased by the difficulty of procuring earth in convenient situations for the purpose, and for the same reason it would be unadvisable to embank any portion of the low bottom of the creek; an aqueduct would, therefore, be necessary, to the full extent of 400 feet, which is the breadth of the creek at this point. The landing place on the cast shore, is only 23 feet high, for the first 80 or 90 yards, which would require, therefore, a heavy embankment. The ground then becomes more elevated; but its height is still insufficient, and would require considerable embanking for 240 yards further. Under all these circumstances, the crossing place at Rich Hill, is considered decidedly preferable, having, at least, less embankment, a much more convenient supply of earth, and nearly two-thirds less aqueduct The graduation of the level for the embankment and aqueduct, is determined, as in other cases, with some reference to the ground in advance. In examining its character for this purpose, it appears that a line, at any reasonable elevation, cannot so conveniently be carried out to the surface of the ground, as by a deep cutting north of the village of Fairview. The extreme elevation on the line of this cutting, is 108 feet above the creek, at the crossing place, and from a careful comparison of its length and volume, under various suppositions with those of the embankment, having in view also, the character of the ground on the route eastward, the crossing is established at 713 feet above the water of the creek: or which is the same thing, 1604 feet above Lake Erie. This leaves 37 feet for the greatest depth to the top water line, on the deep cutting of Fairview. The elevation of our line, in approaching the valley at Hall's run, taking into consideration the declivity of the surface, from the summit to this point, is 306 feet above Lake Erie; and the above graduation gives, therefore, 145 feet, as the total descent to be effected by the lockage on the west side of the valley. This descent it is proposed to distribute in 14 equal lifts, down the side and bottom of the valley of Hall's run, by an arrangement which was suggested, and appears singularly favoured, by the circumstance of the ground. The first lockage leads by a slight, deep cutting, into the head of a large, deep gully, which descends exactly in the direction of the route. This may be divided by dams and locks, into six successive basins; from the last of which, a short oblique cut to the left, leads into another gully, capable of affording two more basins of the same kind. Two others may be added, by the construction of a single lateral dam, under favourable circumstances; and we have a complete chain of ten locks following each other in rapid succession, with a descent which brings the line nearly to the bottom of the valley at this point. The peculiarities of this arrangement are, that, with the exception of the short cut and lateral dam just mentioned, only four of the locks, and a very small portion of the canal, requires any excavation worth notice. Only three of the former, will even require breast walls, as the declivity af fords, generally, an easy, natural descent, from chamber to chamber. The only possible ground of objection, is the rapid succession of the locks. The clear distance from wing to wing, being only 184 feet; but they are still made independent of each other, by the enlarged width and depth of the basins, the former of which can, with perfect convenience, be made as great as 30 yards at the top water line, and the latter, from 6 to 15 feet. We are thus fortunately enabled to connect into a valuable auxiliary, the very circumstance from which the greatest embarrassments were expected, in the construction of this lockage. Should a more gentle descent, however, be desired, it may probably be found by exploring to the right of the present location, and then connecting the line accordingly, as far back as the east branch road. On the east side of the creek, the construction of the line presents nothing particular or difficult, south of the ridge road. At that point a very short tunnel, or deep cut and bridge, is necessary for passing under the road, and avoiding a sharp turn round the point. Three hundred yards further north, the deep cutting commences, and continues 283 perches, to the end of this section, where it runs out in the bottom and Hagerty's run. Totol length of the section, from the head of the grand lockage to the end of the deep cut, at F, 3 miles and 239 perches. 5th SECTION. From Hagerty's to Walnut Creek. This passes in its whole length, upon a level bench of ground, at the foot of the north slope of the ridge upon which the ridge road passes, from which a number of copious springs issue, and afford a considerable addition to the supply of water. No locks accrue; and the only construction of any account, is a culvert, and moderate embankment at Trout run, and a short feeder for the introduction of that stream. Total distance, 5 miles 294 perches. 6th SECTION.-The crossing of Walnut Creek. I have already made some remarks upon the character of this crossing, as a work of labour and expense, rather than of any great professional difficulties. It is a simple gulph of about 180 yards extreme width, and nearly 100 feet deep, but with bold, regular banks, rising on the west side fully, and on the east nearly to the level of the adjacent country. The point selected for crossing, is precisely that at which our level line struck the bank, and a little south of the land line which forms the south boundary of the lake range of lots. Its extreme width at the top of the banks, is 171 yards, and at the bottom 60 yards, and its depth 974 feet below the graduation line of the canal. On 120 yards of this width, it is proposed to construct an aqueduct of five openings, and to complete the remaining 51 yards with embankments, for which there is plenty of earth, in very convenient situations, on both sides. A moderate embankment of 180 yards, is then only necessary for completing out the work to the upland bank, on the east side. Total length of the whole from G. to H. 67 perches. Another locality for crossing, about 560 yards further up, was examined and measured in comparison with the one just described. To make use of it, however, would require, in ascending and returning, not less than 1100 yards additional length of canal; and it does not appear, from the measurement, to possess any superiority as a crossing place, that would compensate for the inconvenience and expense of this addition. Seventh Section, from the crossing of Walnut creek to Turkey Ridge near Erie. This passes over ground of the same character and equally convenient for the location and construction of the canal, as that west of Walnut creek; two or three slight ridges occur, crossing the route in the course of the first five miles, which render it necessary to retain thus far, the full height of the Elk creek graduation. The last of these is passed in the vicinity of M'Creery's chamber should be kept habitually full, and the lower farm soon after entering the state reserve, and then it is one empty. When this is done boats may lock through recommended as favouring the directness of the route, the whole twenty feet in either direction, in an average to commence locking down. Four locks of 10 feet lift of ten minutes; whereas, other things being the same, a are located from this point to the ridge. The first, a lit-boat cannot lock through twenty feet, by two insolated tle eastward of M'Creery's road; second, between Eld-locks, in less, one time with another, than fifteen minutes ridge's and Green's improvements; the third, at the east and a fraction. The extreme quantity of water for a full branch of the Cascade run, and the fourth at the edge of navigation is the same, being six locks full per hour, the Turkey Swamp. The last renders necessary a short drawn from the superior level in both cases. The only deep cutting at Turkey ridge, but it is nevertheless pre- point of inferiority is in the total working capacity. The ferable, as diminishing by one lift the lockage from this six locksful per hour in two insolated locks, working point to the lake. Short feeders on this section enable together, will pass (in effect) eight boats through twenty us to appropriate the waters of three branches of Cas-feet, whilst the same quantity in the contiguous locks is cada run, and of Ichabod's run. only sufficient for passing six boats in the same time. This would be an objection to their use on the route of a canal intended for a very full navigation, but under ordinary circumstances, and especially at a point where a canal unites with a different navigation, it is presumed a working power of six boats per hour, will be found quite of expense, the contiguous locks have, generally, a considerable advantage. The mode of placing them in the present instance, will be such as to bring the upper lock first in contact with the ledge, giving to the lower one an extreme projection of 200 feet; the upper basin will then be formed by a slight excavation in the top layers of the slate. By giving to this basin a breadth of fifty feet, and a slight additional depth, we may make its length as little as 290 feet from wing to wing, and this will enable us to adjust the level of all the following basins in the most convenient relation to the surface of the ground. It now only remains to explain the mode of descend-sufficient. It should be remarked farther, that in point ing into the basin of Presque Isle. For this purpose three routes have been mentioned; the first by Mill creek, on the east side of the town; the second by a gully passing through the public square; and the third by the gully of Lee's run, on the west side of the town. As the first of these would be considerably greater in length than either of the other two, and as it promised no particular advantage, either on the score of construction or local accommodation, being also attended with the inconvevenience of shallow water at the mouth of the creek, I did not think it necessary to bring it strictly into comparison with the other two. Of these, the first named had the appearance of descending rather rapidly, for convenient lockage, from the public square to the water, and upon trial this was found to be the fact. It is also objectionable as affording too little space in width, for the construction of the necessary locks and basins. The last named, viz. The gully of Lee's run was explored with much greater confidence of a satisfactory result. It affords generally, a shorter and more direct route to the basin than either of the others; its declivity though great, is within practicable limits; its breadth is generally sufficient for the construction of the works, and finally, the point of its communication with the basin at the navy wharf, perhaps more favourable than any other, to the local as well as the general interests of the canal in all respects. The lockage remaining to be distributed from Turkey ridge to the lake, is exactly 120 feet, allowing for the descent of the top water line from Elk creek to this place. This is distributed down the bottom of Lee's gully in 12 ten feet locks. The space is not insufficient, and the distribution could be made with perfect regularity to the end, were it not that the declivity is intercepted before it reaches that point, by a substratum of (soft friable) slate, ending in a precipice of twenty-one feet at the edge of the water. To meet this difficulty four different modes have been considered. First, to continue the declivity of the canal, by sinking the three last basins into the rock; allowing to the last a slight projection into the lake. Secondly, to embank the whole of the last line with moderate excavation on the second basin, fairly above the surface of the third lock. Thirdly, to construct a lock of twenty feet lift, by means of a lateral reservoir; and fourthly, to construct two contiguous locks exterior to the ledge. It is unnecessary here to detail all the reasoning which has been employed in the comparison of these various modes. The points on which they have been compared, are first the expense; secondly the practical convenience; thirdly, their conformity with regard to expense of water and locking with the other locks of the canal. The result is a decided preference for the method of the two contiguous locks, and it appears, indeed, that contiguous locks when limited, as in this case, to the number two, are in some respects superior to every other mode of lockage. Their attendance requires, that the upper The final completion of the canal at this point will require some enclosure on the side of the bay, for the safe harbourage of the canal craft. For this purpose I propose the following plan, viz. To construct at the distance of 150 feet in advance of the last lock, a mole or pier 300 feet long, extending upward and downward in such proportions as may be determined by the depth of water. It may be strictly parallel to the shore, or converging towards it in a curve, at the extremity, and should be united with the towing path of the canal, on the line of the present wharf by a pier and bridge sufficiently high for boats to pass under it. The construction of a quay on the land side, with other connecting piers and bridge is also a part of the plan, but these are more properly the objects of private enterprise. The length of the section just described, from Turkey ridge to the mole, is one hundred and ninety-six perches: And we are now prepared to sum up the total distance and lockage from the commencement near Cumming's bridge to the same point, viz. The distance 47 miles and 140 perches; about a mile shorter than the road; and the lockage 507 feet in 48 locks; allowing ten inches for the declivity in the top water line produced by the feeding current, from the summit towards Erie. The drawings for illustrating the preceding de scriptions, are first. A general map and profile of the whole route on the scale of one inch to the square mile. Secondly, A series of maps exhibiting the details of the whole, on the scale of five inches to the mile. The location of the route is carefully laid down upon the latter by the same scale, and upon the principle, as far as other conditions would admit, of reducing the la bour of excavation to the smallest possible amount. Should this route be adopted, and the views of the engineer approved, the actual location, except in the Conneaut valley, may be accomplished, (supposing the levels accurate) by the mere tranfer of the measures from the paper to the ground. Before entering upon the general estimate, it will be proper to give some explanations relative to the construction of the works in masonry. The scarcity of materials has already been alluded to. No stone of a sufficient good quality for the works having been seen on the whole route west of Walnut creek. Still, however, there is reason to believe that |