had the matter fully investigated. Two plank roads were traced built across a moor. One of them showed signs of having been demolished by force, the boards, that originially were fastened to the bearers with trenails, having been violently torn away and buried in the bog. The other road seemed to have fallen into decay, but it appears to have been repaired during the Roman period. Those repairs, apparently, were done hastily, for in one place, a mallet, probably used to drive home the trenails, was found on the track. The local archæologists feel assured that they have here the "Pontes Lougi" which were used A. D. 15 by the Roman commander in his retreat from Germany to Ems. In addition to the 600 miles of roads, such as I have referred to, six bridges were built which in those days were considered important structures; and six harbours, with lighthouses, four on Lake Erie and two on Lake Ontario, including the Burlington Bay Canal. The building of these harbours was a strong incentive to the movement for obtaining still more rapid communication to these points for shipment of agricultural products. Railways now extend to all of them. All these roads and works were completed about the year 1846. These references to the earlier stages of work for facilitating traffic, and to the condition of the country when in course of development, are given with the view of supplying some historic reminiscences, for the purposes of comparison with the present advanced state of public works, as well as those of private enterprise, accomplished by the aid of civil engineers. After 1841 and 1842 there was a rapid development throughout Canada of large enterprises undertaken by the Government and private organisations. The first enlargement of the Welland Canal to 9 feet of water on the mitre sills was commenced in 1842. The earliest railway in Canada, the Laprairie and St. Johns, was built in 1836. The Montreal and Lachine Railway was opened and worked with imported English equipment in 1847. The St. Lawrence and Atlantic Railway (now the Grand Trunk), of which I was chief engineer, was opened for traffic to St. Hyacinthe in 1849. The first deepening of the straight channel in Lake St. Peter, upon which I reported with Sir William Logan, General McNeil, and Captain Child of the U. S. Engineers, was begun in 1850. The Byetown and Prescott Railway, known as the St. Lawrence & Ottawa, now part of the Canadian Pacific Railway, was commenced in 1851, and in the same year, the Northern Railway from Toronto to Owen Sound, as was also, about the same time, the Great Western Railway from the Niagara River to Windsor (now Grand Trunk). I will not enter into further details. These improved means of communication, not only within the boundaries of the Dominion, now extending from the Atlantic to the Pacific, but with the neighboring Republic, have had a marvellous effect in accelerating the material progress of Canada by developing her natural resources in soil, forest, and mine, by stimulating manufacturing industries, and creating those commercial enterprises which have added so greatly to the stability and wealth of the Dominion. The canals of Canada, as a system of internal navigation, have not their equals in the world. As they add so largely to the carrying conveniences of the country, they reflect much honour on the engineering skill displayed in their construction. The St. Lawrence and Niagara Rivers are spanned by bridges that demanded engineering skill to design and erect. Canada has now in operation within her borders no less than 13,410 miles of railways, representing a capital of $727,180,443. In this vital necessity of rapid locomotion, the Dominion with its five millions of people is as fully and favourably equipped as the States with sixty-five millions. It is interesting to mention that in a book published a few months ago, entitled "The Railways of England," by W. M. Acworth,-a work evidently popular, for I quote from the 2nd edition,-the year 1843 is named as marking the period of stable equilibrium and development of railways in Great Britain. At that date there were only 1829 miles in operation, nine-tenths of that mileage was in England. The capital authorized at that date was about £70,000,000, about 300,000 passengers were carried every week, and the total weekly receipts from all sources were somewhat in excess of £100,000. To-day there are nearly 20,000 miles of railway lines in Great Britain, seven-tenths of them in England and Wales. The paid up capital exceeds £800,000,000, and the annual receipts are greater than all the capital in 1843. The number of passengers has increased forty fold. But vast as has been the development of Canada's capacities for meeting the needs of agricultural, mineral and industrial enterprises, and for providing the conveniences of ever enlarging commerce and of domestic life, the future will see even greater strides made in the material progress of our country. The works that have signalized the past only foreshadow those enlarged opportunities for usefulness and distinction which the future will open up to the civil engineer. Permit me in conclusion to say a few words about our Society. The report of the Council shows a considerable increase in our numbers, This no doubt is highly satisfactory, from my own point of view, not only because of this increase, but as a proof that the Society is doing work that is appreciated by engineers, and that the work is good, for were F it otherwise they would not have joined us. During the year of my office as your President, I have to regret that owing to my residing at so great a distance from the head-quarters of the Society, and for other reasons beyond my control, I have done but little towards promoting the interests of the Society. This failure to do more has been from inability and not from earnest good-will towards or interest in the welfare of the Society. Allow me, however, to say that any effort of your President alone will not suffice to ensure success. He is powerless unless aided by members. Pardon me if I say that it is the duty of each one of you to help. Each member should bring before the Society every subject of interest connected with our profession of which he has experience in the course of his practice. He ought to attend the meetings for the reading and discussion of papers as frequently as possible. You will forgive me for these words of personal advice to every member. Although they come from one who was your nominal head but for the short term of twelve months, he is not wanting in age in other ways, and let me assure you that they are inspired solely by a desire that the transactions and papers selected by the Council for discussion should be worthy of the Society. They are the proper medium by which the Society's usefulness is to be maintained. By the printing and distribution of those papers our work becomes known, and by their merits new members are attracted. Accept the assurance that I will do all in my power to further the interests of the Society, and I shall watch its progress with anxious desire to see it prosper. I cannot sit down without making an allusion to the death of my predecessor in the Presidency of the Society, Mr. Samuel Keefer, who was my warm personal friend, and the earliest professional colleague I had in Canada. During the period of my service in the Department of Public Works from 1841 to 1846, Mr. Keefer was my superior officer. I always found his advice sound and most valuable. He was devotedly fond of his profession to which he did honour. He left important engineering works, with which his name will always remain associated. His irreproachable life reached almost fourscore years, the limit allotted to man, leaving a good example to be followed by all members of our profession. Thursday, 30th January. JOHN KENNEDY, Vice-President, in the Chair. Paper No. 37. STAND-PIPES. BY R. S. LEA, STUD. CAN. Soc. C.E. In many systems of water-supply where the reservoir and the pumping station are at a considerable distance apart, a stand pipe is placed upon the force mains, to equalize the resistance against the pumps. The stand pipe, when used for this purpose, serves as a partial substitute for relief valves, acting in combination with tall and capacious air chambers. It is the office of the stand pipe or of the air vessel to take up the excess and to compensate for the deficiency of delivery by the pump pistons, plungers, or buckets, and they are more effective the nearer they are placed to the pump cylinders. The forward stroke of the piston of the single acting pump forces the water, not only along the pipes, but also into the lower part of the air vessel or into the stand-pipe, compressing the contained air in the one case and raising the column of water in the other. The energy stored up in this way is given out, during the backward stroke of the piston, to the advancing water in the main, sustaining its motion until the next forward stroke. The air vessel on the force main is practically a shorter closed-top stand-pipe containing an imprisoned body of air under pressure, instead of a heavy column of water; and neither of them is of so much importance where a double-acting pump is emp'oyed. In such cases the Tall, open-topped stand-pipes of wrought iron or steel are very generally employed, without reservoirs, in the construction of waterworks in the Western States, where the level character of the ground makes them necessary. They are also very often built in locations where the necessity for their use is not so evident. choice between a reservoir, a tank, or a stand-pipe is often one which requires careful calculation, combined with judgment and experience. An earthen reservoir is always to be chosen where practicable, on account of its durable and permanent character. Where the site is just a little too low to enable an embankment for a reservoir to be constructed, at a reasonable cost, a mound of earth is made artificially, and upon this foundation an iron tank is built, which maintains the surface of the water at the required elevation. But in flat countries, or in situations where the nearest elevation is at too great a distance, some other method must be employed to get the requisite head. This may be done either by building a steel or iron stand-pipe high enough for the purpose, or by constructing an iron tank of large diameter compared with the stand-pipe, and supporting it at the proper elevation by a well braced iron tower. One advantage urged in favour of the elevated tank method is, that by making the diameter say 75 per cent, greater than that of the stand-pipe, a much larger quantity of water at a high pressure is always in readiness. This is of importance in case of fire, and this after all is just when pressure is most needed. The delay in pumping up, when the level of the water has been allowed to fall considerably, is one of the strongest arguments against stand-pipes. However, this disadvantage may be obviated by the use of a device for automatically disconnecting the stand-pipe from the distributing main in cases of emergency, several of which have been invented. There are many rules for finding the thickness of the plates of which the shell is made. The following one, which is sometimes used for steam boilers, allows for rivetted joints, and assumes a net strength of 6000 lbs. per sq. inch, and reads: "Multiply the diameter in feet by the pressure in lbs., divide the product by 1000, and the quotient will be the thickness in decimals of an inch." This not very explicit rule, however reliable it may be in the case of boilers, does not work very well in the case of stand pipes and tanks, with their extreme range of pressures and proportions. For example, the stand-pipe in Sandusky, Ohio, is 25 feet in diameter and 208 feet high; this rule would make its lower sheets 24 inches thick, while in reality it has stood for years with a thickness of of an inch. And again, in the case of a stand pipe 5 feet in diameter, the sheets near the top, when the pressure is only 1 lb., would be of an inch thick, i.e., thinner than the thinnest tin plate. 1000 The following formula, in which a constant is introduced, is simple and seems fairly reliable: hx d +.2 t in which h head of water in feet, d = diameter of pipe in feet, and |