196 DEPARTMENTAL BEPOETS. 



completed, and the recommendations resulting from it will be pre- 

 sented to the State legislature for its consideration. 



FOREST PKODtrCTS. 



General Aim of Woek. 



Work under Forest Products during the past j^ear followed two 

 lines: First, studies of methods of timber preservation; and, second, 

 tests to determine the strength of timbers. Timber-preservation stud- 

 ies were grouped by regions into Western, Central, and Eastern. The 

 timber test work was conducted at New Haven, Conn., Washington, 

 D. C, Lafayette, Ind., and Berkeley, Cal. 



In addition, a three-months' investigation was made by the chief of 

 the division in various European countries, of the methods there in use 

 for seasoning and treating woods and for fastening rails to ties. The 

 latter subject is one of vital importance in connection with the use of 

 soft timbers in the United States at the present time. A large amount 

 of information was collected, part of which was published in Bulletin 

 No. 50 of the Bureau. A further bulletin is in preparation dealing 

 with some problems relating to treatment. As a result of this trip, 

 tests are now being made in various parts of the United States to deter- 

 mine methods for more economically treating timber and to ascertain 

 how screw-spikes and screw-dowels ma}^ be made to increase the service 

 of softwood ties. 



An obscure cause of deterioration of ties treated with zinc chlorid, 

 when laid in the track, was made the subject of investigation. A 

 deleterious action which had been observed to affect both the tie and 

 the spike, and which was ascribed to a supposed production of hydro- 

 chloric acid, was found to be really due entirelj^ to electrolysis. 

 Microscopic study of spikes from various mills which were found to 

 behave differently' from one another led to further discoveries which 

 indicate that in the light of these experiments makers of spikes can be 

 so instructed as to produce, at a cost not greater than that now paid 

 for the ordinar}' spike, a spike which will entirely resist the action of 

 zinc chlorid. 



An investigation of the production and use of creosote oils in this 

 country and in Canada, and of the causes of their differences in qual- 

 it3% has brought out the fact that these differences are due to different 

 methods both of treating the coals and of distilling the coal tar. It 

 has also disclosed that market conditions in this country are at present 

 unfavorable to the production of very high grade oils here, because 

 such oils must be distilled at a high temperature. Pitch and creosote 

 oil are both products of the same operation, and distillation at a high 

 temperature ruins the soft pitch which is now in great demand here, 

 and produces a hard pitch which can not here, as it can abroad, be 

 profitably marketed. With a market for hard pitch, high-grade oils 

 could be obtained. 



It was found that the large Canadian supply of these oils which 

 exists is unfortunately of such a character that its use can not be recom- 

 mended excepting for the impregnation of railroad ties. 



One of the most difficult tasks which this office has undertaken has 

 to deal with the action of various chemicals on wood. Numerous 

 experiments were carried on in order to test the formation of insoluble 



