leading up to the signing of these agreements which clearly indicates the employes' acquiescence therein.

It has been shown that no laborers were furloughed at Birmingham, Alabama, due to coach cleaners performing laborers' duties. Consequently, there is no compensation due the employes, as claimed. Furthermore, no laborers are now furloughed at Birmingham, as stated in the employes' claim.

Based on the showing made hereinbefore, the claims of the employes should be denied. The Seaboard Air Line Railroad respectfully requests the Second Division to do so.

FINDINGS: The Second Division of the Adjustment Board, upon the whole record and all the evidence, finds that:

The carrier or carriers and the employe or employes involved in this dispute are respectively carrier and employe within the meaning of the Railway Labor Act as approved June 21, 1934.

This Division of the Adjustment Board has jurisdiction over the dispute involved herein.

The parties to said dispute were given due notice of hearing thereon.

Prior to May 1947, carrier employed ten coach cleaners at Birmingham, Alabama, who were under the agreement with System Federation No. 39, Railway Employes' Department, A. F. of L. They were assigned to clean coaches, and when not engaged in coach cleaning, to clean up around the shop and buildings and perform other unskilled work on the repair track in the car department. In May 1947, carrier placed the Silver Comet, trains Nos. 33 and 34, in passenger service in and out of Birmingham, arriving at 10:45 A. M. and departing at 2:00 P. M. Due to the short turnaround time, carrier placed five additional coach cleaners in service. From 7:00 A. M. to 10:45 A. M., the thirteen assigned coach cleaners do the clean up and other unskilled work hereinbefore described. This claim is made by laborers who are within the agreement between the carrier and the Brotherhood of Firemen and Oilers, Roundhouse and Railway Shop Laborers.

The work performed by the coach cleaners in cleaning up around buildings and shops, and the unskilled labor performed on the repair track, is clearly work assigned to laborers. It is a violation of their agreement to assign this work to members of another craft.

Carrier relies upon Rule 142, current agreement with the coach cleaners which states:

"Coach cleaners to be included in the agreement and will receive overtime as provided herein. Coach cleaners at outlying points may be worked eight (8) hours within a period of ten (10) consecutive hours.

They may be assigned to any other unskilled work during their eight-hour period of service."

We point out that this rule is between the coach cleaners and the carrier, but is no part of the controlling agreement with the shop and roundhouse laborers. It protects the carrier against claims by coach cleaners in the performance of unskilled work as set forth in the last sentence of the rule, but it is wholly ineffective to protect against claims by laborers having an agreement to perform the work.

Carrier contends that it has been the practice for many years to assign unskilled work to coach cleaners to fill out their assignment. This appears to be true, but the extent of the practice seems to have been .greatly extended when the carrier added five car cleaners at Birmingham at the time the

Comet was placed in service. But in any event it is fundamental that a practice will not change the plain words of an agreement. A violation, mutually adopted by the parties, has the effect only of estopping claims prior to the date that one of the parties insists upon compliance with the agreement. When the agreement is indefinite or ambiguous, the practice may then constitute a controlling guide as to what the parties meant when the agreement was negotiated. But when the agreement is clear, acquiescence in the violation of an agreement operates only as an estoppel against retroactive reparations.

We are obliged to say that Claim (1) should be sustained as made.

Claim (2) is sustained as to all unskilled work performed by coach cleaners subsequent to the date claim was made to the carrier by the employes for this work. We decline to direct restoration of any furloughed employes. We merely hold. that the work in question belongs to shop and roundhouse laborers.

AWARD