90 EXPERIMENT STATION RECORD. [Vol. 4:i 



hauling with the teams, when the length of haul is greater than the average haul 

 of 100 ft. and on poor roads and steep grades where teams must be given fre- 

 quent rest periods. As the length of haul gets shorter and the roads and grades 

 improve, the teams will prove the cheaper. 



Agricultural machines essential for rational cultivation, B. H. Hunni- 

 CUTT (.46- Machvnas Agricolas Esuenciacs para um<i Lavoura Racional. Rio de 

 Janeiro [Brazil]: Mendes, 1919, 2. ed., pp. 37, figs. 23).— \ number of different 

 agricultural machines for seed-bed preparation, planting, and cultivation, includ- 

 ing plows, harrows, seeders, and cultivators, are described and illustrated, and 

 discussed with reference to their use in Brazilian agriculture. 



A machine for trimming camphor trees, G. A. Russell (U. S. Dept. Agr., 

 Dept. Circ. 78 (1920), pp. 8, figs. 4). — This machine is described and illustrated 

 and consists of six essential parts, as follows: (1) A truck fitted with proper 

 framework of iron for the conveyance an-,1 support of the operating machinery, 

 (2) an internal-combustion engine on the framework of the truck, (3) a cutting 

 frame consisting of supports for the cutter bar and rocker arm, mounted on 

 the framework of the truck and supported by springs which tend to lessen 

 vibration, (4) a cutter bar held rigidly to the proper angle for cutting, with 

 knives operated by means of gears, pitman rods, and rocker arm connected in 

 the proper manner with the internal-combustion engine, (5) a reel for whip- 

 ping the small camphor twigs, branches, and leaves into the cutting blades, 

 and (6) canvas aprons to convey the several twigs, branches, and leaves into 

 burlap bags carried at the rear of the truck and to dispose of this material in 

 any manner desired by the operator. 



The development of a standard refrigerator car, M. E. Pennington (A. S. 

 R. E. Jour., 6 {1919), No. 1, pp. 1-24, fio^- 7). — This is a brief description of 

 the essential features of the standard refrigerator car designed by the Bureau 

 of Chemistry of the U. S. Department of Agriculture to protect perishables in 

 transit. 



Concrete farm buildings (Concrete Utilities Bnr. [Pamphlet^, No. 8 [1919], 

 pp. 29, figs. 19). — This pamphlet deals with tlie construction of concrete farm 

 buildings, including barns, cow-houses, and silos. 



Concrete poultry houses and piggeries (Concrete Utilities Bur. [Pamphlet}, 

 No. 7 [1919), pp. 16, figs. 12). — Brief popular information is given on the con- 

 struction of concrete poultry houses and hog houses. 



Concrete greenhouses, hotbeds, and root cellars (Concrete Utilities Bur. 

 [Pamphlet], No. 10 [1919], pp. 12, figs. i2).— Brief popular information on the 

 construction of greenhouses, garden frames and hotbeds, and root cellars as 

 practiced in England is given. 



Concrete paths and pavements, curbs, and gutters (Concrete Utilities 

 Bur. [Pamphlet], No. 4 [1919], pp. 16, figs. 16).— Practical information and 

 working drawings are given for use in the construction of concrete sidewalks, 

 curbs, and gutters. 



Concrete troughs and wells (Concrete Utilities Bur. [Pamphlet], No. 9 

 [1919], pp. 17, figs. 15). — Brief popular information on the construction of 

 concrete watering troughs and concrete linings and curbs for open wells 

 is given. 



The construction of cattle dipping tanks (Nairobi: Pub. Works Dept., E. 

 Africa Protect., 1918, pp. 1-15, 19-35, pis. 5).— Detailed instructions and draw- 

 ings are provided for three types of cattle dipping tanks, showing methods and 

 operations to be used in construction. 



The materials for the three types of tank described are concrete, masonry, 

 and timber. It is stated that the concrete tank is the most expensive, but is 

 the most permanent and requires a minimum of maintenance. A well-built 



