A Decexxiat. Recokd .53 



The laboratory's experience in the grading of structural timbers 

 and in the utilization of many of the woods used in shipbuilding was 

 called upon in the drafting of new grading rules for ship timbers 

 adopted by the Emergency Fleet Corporation and in the revision of 

 the rules of construction laid down by the American 'Bureau of Ship- 

 ping. Assistance was also rendered in the inspection of timber under 

 the rules of the Kmergenc}' Fleet Corporation and for the same 

 organization specifications for creosote and its application were pre- 

 pared. These specifications permitted the use of all suitable creosotes 

 and made the corporation independent of various expensive proprie- 

 tary preservatives originally specified. 



A shortage of treenail stock and of properly seasoned treenails 

 seemed imminent in the spring of 1918, and the laboratory was called 

 upon to find new kinds of wood and to specify means of artificially 

 seasoning the treenails. This problem was of first importance since, 

 for a time, the su])])ly of treenails actually determined the rate of ship 

 construction at a number of yards. Certain promising species were 

 selected for experiment, and driving tests made to determine their 

 suitability. Live oak and osage orange were selected as comparing 

 favorably with l)lack locust, and specifications were adopted allowing 

 the use of these woods and })roviding for a better system of inspection. 

 Experimental Mork upon the kiln drying of these species was pushed 

 by the laboratory and the Fleet Corporation made extensive prepara- 

 tions for the kiln drying of live oak treenails, which were abandoned 

 on the signing of the armistice. 



Coopcraiion With the liailroad Adniimstratiou 



The shortage of coal-tar creosote interfered seriously with the 

 wood preservation industry, particularly the railroad branch. An 

 analysis of existing records of the service rendered by treated ties 

 throughout the country was made in connection with a study of rain- 

 fall, and it was possible thereby to recommend the use of zinc chloride 

 in a number of localities in place of creosote. This formed the basis 

 of the allocation of creosote to the railroads by the Railroad Adminis- 

 tration. Specifications for a creosote to be used in the joints in car 

 construction were also submitted. 



