1918.1 RURAL ENGIICEERING. 893 



more important hardwood species native to this country. The experiments 

 were made at the Forest Products Lahoratory maintained by the Forest Service 

 in cooperation with the University of Wisconsin. 



The subject matter is discussed under the following general headings : Struc- 

 ture of the hardwoods, methods used in the experiments, apparatus, materials 

 used, method of applying the creosote, factors affecting penetration, effect of 

 structure on penetrance, grouping of species, relation of grouping to commercial 

 treatment, and conclusions. Notes on the characteristics of the various species, 

 together with the results of the tests and a bibliography of related literature 

 are appended. 



The farm machinery situation, E. A. White {Illinois Sta. Circ. 210 {WIS), 

 pp. 4). — The need under present conditions of careful overhauling of farm ma- 

 chinery and early ordering of new machinery and repairs is emphasized. 



Gas engine nomenclature {Oas Engine, 19 {1917), No. 10, pp. 504-513). — 

 This is the report of the nomenclature division of the data committee of the 

 National Gas Engine Association. 



[Magnetos for farm engines], C. V. Huix {Power Farming, 26 {1917), Nos. 



7, pp. 25, 82, SIf, figs. 9; 8, pp. 24. 34. 35, figs. 8; 9, pp. 85. 36, 40, figs. 9; 10, 

 pp. 42, 48, 45. figi<. 7 ; 11, pp. 16, 36, 37, figs. 6).— This is a series of five articles 

 on magnetos for farm engines. 



The relations of port area to the power of gas engines and its influence on 

 regulation, .T. R. Du Priest {Gas Engine, 19 {1917), Nos. 7, pp. 357-364; 



8, pp. 397-399, figs. 14). — Experiments are reported the object of which was to 

 present a method of determining the port area required for any fractional 

 load on a throttling gas engine operating on the four-stroke cycle and to sug- 

 gest a means of so admitting the fuel as to get the same degree of speed regula- 

 tion throughout the full range of load. 



From a consideration of data obtained in tests of a horizontal double-acting 

 tandem throttling engine, operating on natural g«is, and the characteristic curve 

 of the governor used, a method was devised by means of which the relation 

 between the travel of the governor eollar and port area for a given power can 

 be determined. This is expressed mathematically and by tabular data. 



A new fuel for internal-combustion engines {Brit. Patent 1719 {1916), 

 Mech. Engin., 39 {1917), pp. 813, 314; »&«• in ^oi. Abs., Sect. B-Elect. Engin., 

 20 {1917), No. 235, p. 220).— A British method for starting and running in- 

 ternal-combustion engines is described in which the fuel can be prepared in a 

 plastic state from ingredients independent of oil fields. One composition con- 

 sists of 41 parts potassium nitrate, 41 parts charcoal, and 18 parts sulphur 

 with moisture to make it plastic. The most important feature is the method 

 for obtaining partial combustion to provide a residue of energy after the first 

 stage, to be used in a second cylinder by the addition of air or oxygen. The 

 second combustion stage may be further subdivided. The products of partial 

 combustion are mainly carbon raonoxid, methane, and hydrogen, diluted with 

 nitrogen and carbon dioxifl. An example of the use of this fuel is in the start- 

 ing of an engine for which large air compressors would be necessary. By 

 igniting a cartridge of solid fuel an independent re-servoir can be immediately 

 charged with gas at high pressure and used for the engine. 



How to lay out and put up a lineshaft, R. H. Smith {Power Farming, 26 

 {1917), No. 11, pp. 9, 41, fig. i).— The details of this process are here given. 



The use of rope on the farm, V. Overholt {Agr. Col. Ext. Bui. [Ohio State 

 Vniv.l, 12 {1916-17), No. 5, pp. 48, figs. 757).— This bulletin is published for the 

 instruction of farmers and .students and deals with rope materials and con- 

 struction ; kinds, weight, and strength of rope; coiling and uncoiling of rope; 



