It seems very necessary to increase the foundation area supporting track, when the weight of rolling stock has been increased from 200 to 300 per cent. during past 20 years, and the only increase in track supporting area has been about 33 per cent., due to the closing up ties from about 24 in. to 18 in. centers.

Mathematical calculations of tie stresses are of doubtful utility, because of the number of variable and unknown factors in actual practice, so that experiments under actual service conditions seems the only reliable way of getting accurate data. The difficulty is to get railway companies to supply the funds for such experiments.

The investigations made by Ast and Blum, referred to in the Committee's report, indicate that ties 8 ft. 10 5/16 in. long, 104 in. wide, give good results on German and English railways, where axle loads are much less than on this continent. These investigators also state that "the superiority of the long, stiff sleeper becomes more apparent the less good the ballast is."

Of course the length of ties is not so important when rock ballast is used, but as the majority of railways still use gravel ballast, the writer would suggest that some of the leading railways might, or should, make experiments under actual service conditions on short sections of track with 10 ft. ties. This length gives practically the same distance from center of rail to end of tie and center of track, and while giving 25 per cent. more Supporting area than an 8 ft. tie, would not require much, if any, more ballast, as the ordinary 15 ft. base of ballast with convex top would be sufficient for this length of tie, and the increased length of tie would occupy space otherwise occupied by ballast. (The attached drawing illustrates this.) Ten ft. seems the logical length, as the functions of the tie are to hold the rails in place relative to each other, and to distribute the loads through the ballast to the subgrade in such a manner as to prevent the crushing of the ties abnormally far into the ballast or of the ballast into the subgrade.

If we assume the ties sawn completely through at the center of the track, and spreading of track prevented by steel rods bolted to the rails, then the ties would only have to support the axle loads applied vertically through the rails. Eight ft. ties cut in center would project 2 ft. 51⁄2 in. inwards from center of rail, and 1 ft. 61⁄2 in. outwards, and doubtless these outer ends would sooner crush down into the ballast than the inner ends. With 10 ft. ties the length each way from the rails would be practically the same, and would surely equalize and minimize the unit pressure on the ballast and the subgrade. It would doubtless cost more for the longer ties, but at present prices they cost per mile only about 35 per cent. of the cost of 80-lb. rails and fastenings, and the weights of the latter are constantly increasing. The life of this more expensive part of the track and rolling stock could be considerably increased, with the better track conditions due to longer ties, so that it would seem true economy to spend a little more on ties rather than to continue increasing the cost of the expensive superstructure while leaving the comparatively cheaper foundation defective.

1/2 to

Note:-Eight ft. ties tamped firmly for 16 in, each way from rails only utilizes the supporting area of 77 per cent. of tie equal to 74 in. in length, or 740 sq. in. for a tie of 10 in. face.

Ten ft. 0 in. ties could be used in the same ballast section, firmly tamped for the whole length; giving the maximum supporting area of 1,200 sq. in., or equal to 162 per cent. the efficiency of 8 ft. ties.

I've to

DIAGRAM ILLUSTRATING HOW TIES IO FT. O IN. LONG MAY BE USED IN AN ORDINARY BALLAST SECTION FOR 8 FT. TIES WITHOUT REQUIRING

ANY EXTRA BALLAST.

DISCUSSION ON SIGNS, FENCES AND CROSSINGS.

(For Report, see pp. 791-830.)

LIST OF SPEAKERS TAKING PART IN DISCUSSION ON SIGNS, FENCES AND CROSSINGS.

F. J. BACHELDER.

J. L. CAMPBELL.

A. W. CARPENTER.

ROBERT FERRIDAY.

RICHARD L. HUMPHREY.

J. B. JENKINS.
S. A. JORDAN.
F. P. PATENall.
E. V. SMITH.

C. H. STEIN.

The President:-The report of the Committee on Signs, Fences and Crossings will be presented by the Chairman, Mr. C. H. Stein.

Mr. C. H. Stein (Central of New Jersey) :-The Board of Direction assigned to this Committee for consideration during the past year the following subjects:

"(1) Report on the relative advantages of the different kinds of fence posts, with definite recommendations.

"(2) Report on the best form of track construction and flangeways at paved street crossings and in paved streets, with definite recommendations.

"(3) Continue the investigation of ways and means for securing a proper quality of fence wire to resist corrosion and secure durability." You will observe in two instances that the Board of Direction indicated a growing impatience with the Committee in not seeming to at least endeavor to dispose of these two subjects that have been given it for the past several years. The Committee aimed, in view of the fact that it was the only one of the committees that had received such mandatory instructions, to gather together everything available that had reference to these subjects; they investigated the matter of the different kinds of posts made from wood, steel and concrete, collecting such data as they could from the railroads and securing all the information that was available on this subject, with a view of presenting definite recommendations.

It seems to us that this particular subject pointed inevitably to the consideration of concrete for fence post purposes and after considering all the available information the Committee embodied its ideas in a series of conclusions which will be found on page 816:

(1) Concrete posts are practical, economical and a suitable substitute for wood.

(2) Reinforcement should be placed as near to surface of post as possible; 2-in. from surface is best location.

(3) Post should taper from base to top.

(4) Post should not be less than 51⁄2 in. at base and 4 in. at top. (5) Concrete mixture should consist of one part cement to four of run of pit gravel; or one part cement, two parts sand and four parts

crushed rock or screened gravel. Gravel or crushed rock not to be smaller than 1/4-in. in size, nor larger than 2-in. Concrete should be of a quaking consistency.

(6) Molds should have a jogger or vibratory motion while concrete is being introduced to compact it and smooth up surface of post.

(7) Posts should not be made out of doors in freezing weather. They should not be exposed to sun, and should be sprinkled with water the first eight or ten days after being made to aid curing.

(8) Molds should be carefully oiled or soaped to provide a smooth finish and to prevent concrete sticking to mold.

(9) Posts should be cured for not less than 90 days before being set or shipped.

(10) Posts should be carefully handled and be packed in straw, sawdust or other suitable material for shipment.

It is to be borne in mind that concrete posts are proprietary articles, and not a great deal of progress has been made among the railroads yet in the consideration of them. There are very few who have gone very largely into the matter, although it seems as if it is growing very rapidly and that better information will be developed in the course of a few years. The farming communities have been more largely users of concrete posts than the railroads. We have endeavored to avoid, as far as possible, any references to the names of the manufacturers of these posts.

We have presented these conclusions as some cardinal principles governing the manufacture of the posts.

Mr. Richard L. Humphrey (Consulting Engineer) :-There is one very essential point which I think the Committee has overlooked. It is recommended that the reinforcement be placed one-half inch from the surface and it is further recommended that gravel or crushed rock should be used as an aggregate. I think it will be found where the crushed stone is rather soft or has high absorptive qualities that there may be trouble encountered through the corrosion of the reinforcement of the post. The gravel or crushed stone used in the post should be hard, dense material, with low absorption, otherwise it may be the means of developing corrosion of the reinforcement and the final destruction of the post.

Mr. Stein:-You understand that these are conclusions only.

I move the adoption of these conclusions, which have been read, sections I to 10, and also the recommendations that the conclusions be substituted for those in the 1911 Manual of Recommended Practice.

The President:-The conclusions in the Manual, heretofore adopted, are quite indefinite compared with these and those now submitted are certainly an improvement.

Mr. Humphrey :-I suggest that we put in the fifth conclusion, "gravel or crushed rock of low absorption."

The President:-The Committee will accept that.

Mr. Robert Ferriday (Cleveland, Cincinnati, Chicago & St. Louis) :-Does the Committee consider it essential or necessary to require, in conclusion 6, that the molds should have a jogger or vibratory motion?

Their idea, as I understand, is to make the surface of the post smooth. Is that the only way that a smooth post can be made?

Mr. Stein: I might say, in regard to that point, as I remarked in presenting this report, these posts are proprietary articles. The railroads have just begun to use the concrete post, and the experience of those railroads, so far as we could learn, who had used the different kinds of posts, is, that those railroads which use molds with the jogger or vibratory motion turned out the best posts, and also that these posts are the most compact; the Committee concluded that, at this time, in the present state of the art, until we get something different, that it is a very essential feature. I believe the United States Government has made some experiments and has reached the same conclusion. Jogging has a tendency to compact the concrete and make it proof against the infiltration of water.

Mr. Humphrey :-The Committee recommends concrete of a quaking consistency. It is my opinion that there is a tendency to make the concrete too wet, and the result is water voids in addition to air voids, which decrease the density of the concrete and, therefore, the strength of the post. It would seem to me that there should be a definite period of time for mixing the concrete, so as to reduce as much as possible the air and water voids. It is possible in this way to secure a concrete of quaking consistency with much less water, which, when vibrated in the mold, produces a concrete of maximum density. The vibration of the post recommended by the Committee is excellent and with a well-mixed concrete great strength may be attained.

Mr. Stein-I will answer by saying that the experience of those who have engaged in the manufacture of concrete posts is just to the contrary, and it has been almost the uniform experience of those who have been making posts, that the concrete should be at least of a quaking consistency, and some very good posts that are turned out are made under a specification that "you shall be able to pour the concrete." The Committee did not see that it was warranted in taking the advance ground that the manufacturers of this very good concrete post took and the Committee thought it was only warranted at this time in specifying that it should be a quaking consistency. We realize that perhaps these are not the best specifications that can be gotten up. Solon, the great law-giver of Greece, in presenting the first laws to the Grecians said, when asked if they were the best he could prepare, "No, they are not the best I can prepare, but they are the best that you are willing to accept." While these specifications may be improved, I do not believe if we made them more radical they would be considered.

This is the first advanced step we have endeavored to take upon the subject of concrete fence posts. We have had a series of principles before that really did not deal with posts, except in a very remote sense. We have tried to present this time something that will be acceptable, but we realize we have only scratched the surface. As the Illinois Central, the Chicago, Burlington & Quincy and the Rock Island roads have undertaken investigations in the matter of the construction of