THE FAKMER AT HOME. 345 



have borne the traffic of nearly two thousand years without material 

 injury. The Romans, always gave a firm foundation to their roads, 

 by ramming down a layer of small stones arid broken bricks ; on this 

 layer a pavement of large stones was laid, either to fit closely around 

 one another, or cemented into a hard and firm causeway. In our 

 own country, as yet, but little has been done in the construction of 

 public highways on scientific principles. Some attempts have been 

 made for the Macadamized roads, and more recently for plank roads ; 

 but the latter, although answering a good temporary purpose, will 

 soon w r ear out. 



The plan of M'Adam has generally been found to be free from the 

 objections most common in previous efforts to construct good roads. 

 His plans, as many of our readers know, is to make a deep layer of 

 small stones which will lock together, by the frequent pressure upon 

 them, into a hard and compact mass, forming a sort of crust nearly 

 impervious to water. The quantity of these small stones must depend 

 on the quality of the ground beneath ; in many cases a layer of two 

 or three feet has been required. In some cases where a deep layer 

 would be indispensable, there has been for a foundation to the small 

 stones, a layer of large ones, carefully disposed by hand, so as to 

 remain without any change of position. It has been found that this 

 affords an easier draught for horses than where the substratum is of 

 earth ; and that a gravel surface is more trying to horses than a 

 broken stone surface. Stone tramways have occasionally been applied 

 in England to common roads with great advantage. They consist of 

 wheel-tracks formed of large blocks of stone, usually granite, over 

 which the wheels roll smoothly, while there is an intermediate broken 

 stone road for the horses. Iron tramways have sometimes been used. 

 It is supposed by many that good tramways, and even Macadamized 

 roads, may be constructed so as to answer the purpose for locomotives. 

 This has been attempted in France, and with a prospect of satisfac- 

 tory results. 



ROLLEH. Hollers are important implements in modern farming, 

 and are fast coming into general use. They crush all the sods and 

 lumps that remain on the top of the ground after the harrow has passed, 

 and force down small stones level with the surface. They render the 

 field smooth for the ;-radle, scythe, and rake, press the earth close 

 about the seed, and secure a more sure and quick germination. On 

 light and sandy soils they are invaluable, and in all cases their use 

 has greatly increased the product. Much benefit is undoubtedly 

 found in compressing the surface of light soils, by preventing the 

 escape of those gases from the manure so essential to vegetation, and 

 which are so rapidly extracted by the sun and winds. 



Great advantage is gained by rolling early in the spring, while the 

 ground is soft. Clay lands, by heaving, pull to pieces and displace 

 the roots of grain and grasses sown the previous autumn, and the 



