288 EXPERIMENT STATION EECORD. 



A discussion is sivon of tlio pnictical details of tile drainago, showinj; how tbe 

 work should l)o plaiinod to meet different conditions, and describinj,' tlie instru- 

 ments \ised in Inyin;: out the systems and tlie tools and methods employed in dig- 

 ging the ditches and laying the tile. The use of machines for digging tile ditclies 

 is considered, with data as to the relative cost of machine and hand labor. 

 Tables are given showing the number and size of tile required to di'ain a given 

 area under si)eciflc conditions and also the cost of the various sizes of tile in 

 common use. 



The value of open ditches and the efficiency of stone drains, such as are used 

 in some parts of the State, are discussed. An appendix presents an abstract of 

 the New York law relative to agricultural drainage and a list of tile manufac- 

 turers in the State. 



Dust preventives, L, W. Page ( U. S. Dept. Agr. Yearbook 1907, pp. 257-266, 

 ?)?s. -'/). — A discussion of the problem of preservation of road surfaces under 

 automobile traffic and of the use of dust preventives, with an account of the 

 results obtained from the use of mineral oils, coal tar, sea water, magnesium 

 chlorld, sodium chlorid, water-gas tai', and a number of proprietary emulsions. 



It is stated that up to the present time no method of building an economical 

 dust-proof country road has been devised. As to the relative values of different 

 substances for the treatment of existing roads, "in certain localities the use of one 

 of these materials is often claimed to be more satisfactory than others. Whether 

 this is due to skill in treatment or to local physical conditions, it is impossible 

 at present to say. In estimating tiie relative cost of dust prevention by various 

 materials, it must be borne in mind that any substance which prevents the for- 

 mation of dust, and holds that already formed on a road surface, greatly length- 

 ens the life of a road and consequently lowers the cost of maintenance. This 

 precludes the obtaining of accurate cost data at present, as it can only be had 

 after a sufficient length of time has elapsed to determine the saving in repairs to 

 the road from the use of dust ])reventives. The entire subject is still in an 

 experimental stage, and where a community wishes to have work of this kind 

 carried on, the advice of some experienced person, familiar not only with one 

 preparation but with many, should be sought in order to avoid costly mistakes 

 and the repetition of failures made in other places." 



The effect of alkali on Portland cement, E. T. Tannatt and E. Burke 

 (Montana Sta. Bid. 69, pp. 93-120, ^j/s. 5, figs. 4). — Examinations of cement 

 structures, particularly sewers at Great Falls, Mont., which had been dis- 

 integrated by the action of alkali, are reported and discussed in this bulletin. 



" Just how the alkali in the soil acts upon the cement is a matter for investi- 

 gation. It is possible that the action is similar to the action of the salts in 

 feea water ... or it may be that the cements behave in a manner similar to 

 the soils containing zeolites. Zeolites being hydro-silicates contain as bases 

 chiefly lime and alumina with some potash and soda, which have the power of 

 absorbing alkali salts and exchanging bases with them." 



The authors conclude from the investigations that the use of cement con- 

 struction for sewers is inadvisable in alkali soils unless it is possible to di'ain 

 all ground water from the exterior of the sewer. Sandstone and concrete 

 foundations for buildings are subject to the same objections. " 



Conditions affecting the production of denatured alcohol in the Northwest, 

 J. S. Jones {Idaho Sta. Bui. 60, pp. 3-21). — A popular discussion is given of 

 the present situation in the Northwest, with excerpts from the Federal laws relat- 

 ing to the production of denatured alcohol, an exposition of some of the regula- 

 tions of the Connuissioner of Internal Revenue, and data as to the efficiency of 

 denatured alcohol for light, heat, and power. Although no denatured alcohol 



