first thing that was done as a remedy was to increase the wheel base, but this did not prove to be of much advantage. The first successful remedy appears to have been made by extending the sides of the truck, and on the extension pieces mounting an elliptic or half-elliptic spring. The latter method with the half-elliptic spring has been the most successful preventive tried. The necessity for overcoming the oscillation was considered so important, and the success of this device so great, that a series of inventions were, and are being, brought out for the purpose of accomplishing the same result. Numberless combinations of elliptic, spiral, and other springs of various kinds were made, and also a large number of inventions involving the use of levers, cross-equalizing bars, and other similar mechanical devices have been made; some of which appeared to succeed, but in most cases failed to produce a satisfactory result. Some of these devices in overcoming longitudinal oscillation very frequently caused the car to ride very stiffly and produced an undesirable effect upon the track. Others gave the car too much lateral motion, apparently, by the conversion of the longitudinal oscillation into a side or lateral movement. The so-called "extended spring base" which is combined with the half-elliptic springs has, in my judgment, been the best solution of the problem up to the present time. It is conceded that the equalization of the wheels to carry the load according to the practice on steam roads is out of the question with a car which has only four wheels. As time went on and experience was gained, one point was gradually made more and more evident-which was that a motor truck was a locomotive in every sense of the word, and for success must be governed in its construction by the same general principles that are involved in the construction of a locomotive machine. The greatest difference between the functions of a motor truck and a locomotive truck seems to be the fact that the motor truck carries the load instead of drawing it. It also has to preserve its propelling machinery in perfect alignment while it is moved forward by the revolutions of its axles, and is subject to combined vertical, horizontal and twisting strains of the most severe kind, and at the same time it must ride as easily as a carriage. It has been demonstrated that a composite truck frame is a failure because of its inability to stand all the strains imposed upon it. The braces, which were amply sufficient to carry the weight, give it no strength to resist twisting strains; then, again, malleable iron parts break, bolts and nuts become loose and rattle, and it is next to impossible to prevent rivets from shearing, and bars from twisting out of their places. The composite frame demonstrated its imperfections with the locomotive years ago, and has been found even less successful as a form of construction for a motor truck. This is due in a measure to the fact that on account of cost, first-class workmanship is out of the question in building a lowpriced truck. The truck frame consisting of a solid forged bar, of course, gives greater strength to resist strains thrown upon it from all directions than any form of a built-up truss. Now, as a result of the best information and from large experience, I believe the ideal four-wheel truck for electric cars at the present time is one having the fewest number of parts in its construction, in which the side pieces of the main frame are single forged bars connected across the ends by bars either bolted or welded on so as to make the frame one continuous piece. This frame is carried by springs from the journal boxes, and itself carries an upper chord, likewise, a continuous rectangular piece which has suitable seats for the springs. This upper chord is recessed to take the bolts and spring seats, leaving its upper surface flush. The ends are carried by the half-elliptic springs, while the spirals are placed at the journal boxes. The brake should be hung by links. Diagonal bracing, on account of the motors, is out of the question in the construction of a truck, but the diagonal strength is usually increased by the introduction of transoms. Such a frame carries its machinery with a certainty of its always being in alignment with the driving axle, and as it is spring carried, it is as light on the rails as any form of single truck, while the longitudinal oscillation is prevented by the peculiar effect of the half-elliptic springs which do not respond readily to rythmic motion. So much for the form of construction of a good type of four-wheel trucks, but what of the disadvantages of four-wheel trucks in general. Taken at its best, the four-wheel truck is an uncomfortable carriage and a veritable track-destroyer, and should only be used, according to the best judgment of many of our wide-awake railroad men, where cars are run at comparatively slow speed, and with moderate length of car bodies. Where it is desirable to run at higher rate of speed in suburban service, the damage to the track becomes so great that it should preclude its use. The increased length of wheel base made necessary makes it hard on curves. The only alternative is to use a double truck car with swivel or pivotal trucks. The advantage of this form of truck is very great, and while nearly everyone is familiar with its good qualities in a general way, I hope I may be pardoned for going into details which are not so well known. They are easy on curves to a degree that would hardly be credited by those who have only been familiar with four-wheeled cars. The greater number of wheels not only reduce the weight on each wheel, but correspondingly reduces the blow when the wheels strike a joint, or a low place in the track. This is still further diminished by what is known as "equalization," which practically places the car body at the central point of the truck so that each wheel in rising or falling in passing over any imperfection in track elevates the load a distance but half as great as its own rise. Oscillation, whether longitudinal or transverse, can be completely done away with by the use of double trucks. While the trucks conform closely to all the irregularities of the line, the body can move forward with but very little influence from them. The conditions, however, are not altogether in favor of the pivotal truck; as, for instance, if all the weight is used for adhesion it is twice as expensive in use as a fourwheeled truck. If two motors are used, it only has fifty per cent. of the propelling power. In its ordinary form, it makes a wide body necessary, and hence is out of place in narrow streets, or places where traffic is very heavy. It also has the disadvantage of putting the body at a greater height than is necessary with four-wheeled trucks. But it meets a great many of the requirements for fast suburban service, and has been endorsed with great satisfaction; but the objection which I have just mentioned precludes its use in many cases where it would have otherwise been desirable. Now the remedy for nearly all these objections has been found in what is known as the "Maximum Traction" truck. The Maximum Traction truck may be defined as a pivotal truck in which the load is eccentrically placed in relation to the four wheels, two of them receiving only a sufficient amount of weight to keep them upon the track, while the others take the remainder of the load. In practice it is found that eighty per cent. of the weight may be placed on the driving wheels, while twenty per cent. is used for guiding. Upon applying these trucks, it was found that it was not necessary to have the wheels of equal size; that a large pair of driving wheels and a small pair of idle wheels can be used. The large pair, used as driving wheels, being very near the pivotal point, have a comparatively small amount of swing, and can be allowed to rise within the floor timbers, while the small wheels, moving through a much greater arc, easily clear the sills. By this form of construction, the body can not only be brought down, but the frame can be made as narrow as in the ordinary street car body. This form of truck enables the car to be utilized for both street and suburban service. It is also found, in its latest form, utilized under long open cars. It carries the motors in a satisfactory manner, guides readily and answers nearly all the requirements of the service. But the question of what form of truck answers interurban service, is one which every railway manager must study for himself. This becomes necessary, because the conditions on different roads vary so much that there are scarcely two in the whole country upon which they are identical. The question of the amount of traffic, and the headway on which it is desired to run cars, involves careful study. With heavy traffic and frequent stops it is necessary to have low cars, from which ingress and egress are easy. An extra step will increase the danger to passengers very much. On the other hand, where passengers are carried a considerable distance without stops, long cars with more than one step are permissible. As interurban service is almost equivalent to that of the steam roads, for this service pivotal trucks, having regular swing beams, equalizers, elliptic springs, and all the parts of the steam road truck, are entirely satisfactory. They take curves easily at a high rate of speed. But for trucks which must run not only on trams, but on T rails, some form of the Maximum Traction truck will give, all things considered, the best service. In conclusion, let me call attention again to this very important question to be considered in connection with the adoption of single and double trucks, which is, whether the punishment to the track by single trucks is not so great as to more than make up for the cost of putting in and running double trucks under cars of all lengths of bodies, whether short or long. Respectfully submitted, JOHN N. AKARMAN. The President: Gentlemen, you have heard the reading of the paper. What is your pleasure? Mr. Bean, St. Joseph: I move that the report be received and spread upon the minutes. Carried. The President: I would be very much pleased to have this paper discussed by gentlemen who have had experience with single and double trucks. I know all want to ask some questions about this paper. Trucks are a very important factor in the street railway business. If there is no discussion on this paper, we will proceed to the next business. INVITATIONS TO FAIR GROUNDS AND MOOLAH TEMPLE. The President: I am pleased to announce at this time on behalf of the Local Committee, that at two o'clock this afternoon cars will leave the Southern Hotel for the Fair Grounds. Each and every gentleman in attendance at the Convention, delegate or supply man, is cordially invited to attend, with their ladies. We expect to have two or three hours' entertainment at the Fair Grounds, with luncheon, music, etc., and we will be pleased to have you all attend. I am also requested to announce that the gentlemen here who are Shriners are invited to meet the St. Louis potentate, Gus. Neiman, at Moolah Temple, at eight o'clock to night. I understand that one of our members expects to cross the Desert, and if you do not see him in the morning, you will know what happened to him. All Shriners are invited to attend, and nobody can appreciate what a Shriner means who is not one. It is like the fellow who took a toboggan slide. He said he would'nt have missed it for a thousand dollars and would not go through it again for five thousand. (Laughter.) INVITATION FROM ENGINEERS' CLUB OF ST. LOUIS. The Secretary read the following letter: H. M. LITTELL, ESQ., ENGINEERS' CLUB OF ST. LOUIS, ( PRESIDENT, AMERICAN STREET RAILWAY ASSOCIATION, Dear Sir:-I am authorized by the Acting President to extend to the members of your Association the privileges of the Engineers' Club Library and Reading Room, at 1600 Lucas Place, during their stay in this city. Our general engineering library and periodicals are at your service. A special invitation is also extended to those of your members who may be interested in the subject, to attend the meeting of the Club, at 8:00 p. m., Wednesday, 20th inst. The business of the day will be the reading of a paper on "Boiler Efficiency, Capacity and Smokelessness, with Low Grade Fuels," by Mr. William H. Bryan. Yours truly, WILLIAM H. BRYAN, Secretary. Mr. Kelly, Columbus: I move that the Secretary be instructed to return the Engineers' Club of St. Louis a vote of thanks for their kind invitation. Carried. The President: As Mr. Wyman is not present to read his paper, which is next on the programme, we will take up the paper on "The Modern Power House," by Mr. Richard McCulloch, Civil and Electrical Engineer, Citizens', Cass Avenue, and St. Louis Railroad Companies, St. Louis, Mo. First Vice-President Robert McCulloch in the Chair. REPORT OF THE COMMITTEE ON "THE MODERN POWER HOUSE." Mr. Richard McCulloch read the report, as follows: TO THE AMERICAN STREET RAILWAY ASSOCIATION, Gentlemen :-In beginning a paper of this kind, it is usually considered proper to start with a sort of historical review, but in this case we are immediately struck with the fact, that, unlike most modern institutions, the eventful history of the street railway power house has been condensed into the last few years. The conditions, the general design, and the greater part of the machinery itself, have been evolved during the last ten years. All of these have changed rapidly and the manager who now deplores as antiquated a power house built six years ago, with the best existing machinery and in the light of the most approved prac |