The Committee has revised the specification for the Preservative Treatment of Wood with Creosote Oil (Empty Cell Process with Final Vacuum), as shown on page 332 of the 1920 Proceedings.

The third paragraph of the specification has been changed to read as follows:

"The material shall retain an average of at least 6 pounds of creosote oil per cubic foot which will permeate all of the sapwood and as much of the heartwood as practical," and no charge shall contain less than 90 per cent nor more than 110 per cent of the quantity per cubic foot that may be specified.

The specifications for creosote oils as now embodied in our Recommended Practice have been subject to some discussion during this past year, and a committee was appointed consisting of R. S. Belcher, H. C. Bell, C. E. Gosline and O. C. Steinmayer. As a result of an investigation covering forty-two different railroads using creosote oil, it was disclosed that a great many of the railroads are using oils which do not fully comply with our present specifications, and the following statement covering the situation has been approved by the General Committee as an indication of the situation:

"The specific gravities of the fractions are inserted as specified in Section five of the various creosote oil specifications to prevent the admixture of any considerable quantities of water gas tar. The limits had to be placed so high in order to prevent this that, as a general thing, the only oils that would meet the requirements are oils produced from coke oven tars and a few gas house tars that are produced under high temperatures and only moderate sized charges. The Committee now finds that a very considerable amount of creosote oil, that is apparently produced from authentic uncontaminated samples of coal tar, will not meet these gravity requirements. This is particularly so with a number of samples of English oils prepared from horizontal tars operated at moderate temperatures or at high temperatures with very large charges, or when produced from vertical retorts.

Furthermore, the Committee has recently been furnished samples of oil produced from the distillation of a petroleum tar that has gravities considerably in excess of those required. The Committee, however, is not in a position at the present time to recommend any simple test that will on the one hand absolutely prevent the addition of water gas tar and that will, on the other hand, permit the use of creosote oil made from all samples of coal tar.

The Committee, therefore, recommends that until the study now in progress by this Committee is completed and report thereon made that the railroads give greater consideration to the sources of tars used in the manufacture of creosote oil in case the specific gravities of the two fractions in question do not fully comply with our present recommended practice.

(2) SERVICE TEST RECORDS

R. H. HOWARD, Chairman; F. J. ANGIER, E. H. BOWSER, S. D. COOPER, C. F. FORD, HERMANN VON SCHRENK, Sub-Committee.

Instructions:

Make final report, if practicable, on Service Test Records, extending them to include treated timbers in Bridges, Docks and Wharves, and include a study of the records of service given by Zinc Chlorine Treat

ment.

Introduction:

The treatment of cross ties and timber of all kinds with some preservative to prevent decay, is growing more important as the available supply of timber decreases.

There are many different chemical preservatives used, and as creosote oil, zinc chloride, and a mixture of these two, are more widely used than the others, these only will be discussed in this report.

Of these preservatives there is no question about the use of creosote oil being preferable. Zinc chloride and a mixture of zinc chloride and creosote oil are used with much success in certain regions.

Treatment:

The attached statement "Exhibit A", supplied by the Forest Products Laboratory at Madison, Wisconsin, gives the results of all completed tests of cross ties of which we have record. There are other tests under way and the completion of these tests will add valuable data to that given in this exhibit.

The Committee is of the opinion that it will be much more desirable in the future to publish nothing but completed tests. It is considered that this is the best method to be used, as everybody interested will be able to get definite information as to service life secured in all parts of the country from cross ties treated by various methods. Completed tests will be reported each year.

Zinc Chloride (Burnettizing) Process:

With the present scarcity of creosote oil resulting in high prices, and the large number of cross ties to be treated, economy demands that some other preservative be used.

For some time there will not be sufficient creosote oil to treat the required number of ties. Therefore, it is imperative that the Burnett Process of treatment be more widely used in order to secure the greatest possible economy in the use of ties.

Below are given the governing features for maximum service life and economy in the use of ties treated by this process.

Conditioning required for satisfactory treatment:

(1) Preliminary seasoning-Be sure that the ties to be treated have been thoroughly seasoned and that decay has not already begun.

(2)

(3)

Proper treatment-To secure this the treatment should be supervised by a competent Treatment Inspector under the jurisdiction of the Engineering Department of the Railroad. Subsequent seasoning-Care should be taken to see that the ties are thoroughly seasoned after treatment. They should be piled in close piles with end ties on edge (as per sketch below), to prevent excessive checking.

(4) All piles should be placed in dry places and kept free from weeds.

Maximum service results will be obtained only upon observance of the following:

(1) Drainage-Good drainage of the roadbed is absolutely necessary to secure maximum results.

(2) Ballast-The ballest should be sufficient and of the best
available materials, and should be kept clean.

(3) Tie plates-Tie plates of proper size and thickness should
be used on all treated ties to prevent destruction by mechani-
ical wear.

(4) Rail anchors-Use rail anchors where necessary to prevent
creepage of rail, and slewing of ties.

(5) Distribution of ties-When practicable use hardwood ties
on curves and softwood ties on tangents.

(6) Tie plugs-Whenever it is necessary to re-spike a treated
tie, treated tie plugs should be applied, and when possible
to do so the spike should be redriven into the tie plug.
(7) "S" Irons-"S" Irons should be applied to hardwood ties
before treatment, preferably in the woods at time of manu-
facture, or, if not then, immediately after the inspection.

The following tables taken from "Exhibit A" indicate the life of ties, treated with zinc, zinc creosote and creosote, taking as a base the service life of ties of different kinds of wood in the various sections of the country. Attention is directed to the grouping of these tests. It will be noted that various methods of treatment are grouped according to the geographical location of the test and the kind of treatment given.

A

COMPLETED TESTS FROM THE RECORDS OF THE FOREST PRODUCTS LABORATORY, MADISON, WIS.

PLETED TESTS FROM THE RECORDS OF THE FOREST PRODUCTS LABORATORY, MADISON, WIS.

COMPLETED TESTS FROM THE RECORDS OF THE FOREST PRODUCTS LABORATORY, MADISON, WIS.