SKILFUL ROAD-MAKERS REQUIRED. 29T 



many experiments, the results contained in the following table ; 

 inserted here for purposes of comparison. The wagon used 

 weighed twenty-one cwt., and the resistance to draught was : — 



On a well-made pavement, . . . . . 33 lbs. 

 On broken stone laid on pavement or concrete founda- 

 tion, . . . 46 " 



On broken stone laid on earth, . . . . 65 " 



On a thick coating of gravel laid on earth, . . 147 " 



These and many other like experiments made in France and 

 Great Britain point clearly to the great superiority of the best 

 broken stone roads, over those made of gravel and loam in the 

 ordinary way. More will be said bearing upon this subject 

 further on. 



Suitable Persons to have charge op Roads. 



To secure such kinds of structures as have been described, or 

 to make material improvements upon those in existence, it ought 

 not to be necessary to intimate that the work must be done under 

 the direction of practical road-makers, whose education and 

 training j&t them for such duties. But the common practice of 

 entrusting such work to those who are not only wholly ignorant 

 of the mechanical principles necessary for the achievement of 

 success, but who have had no experience useful for the duties 

 required, seems to indicate that this consideration is not appre- 

 ciated. 



An extensive knowledge of scientific principles is necessary for 

 the successful practice of the engineering art, of which road 

 making is not the least difficult or important branch. An ac- 

 quaintance too, with the processes and expedients, whether suc- 

 cessful or not, employed by men who have achieved eminence in 

 their profession, is needful to help mark out the right path, and 

 to hint at the direction in which to look for resources in difficult 

 emergencies. No art can, however, be learned from books alone, 

 but the skill to execute, the ability to judge of the qualities and 

 fitness of materials, the ingenuity to overcome difficulities, and 

 the readiness to find and adopt methods of operation suited to 

 each particular understanding must be acquired from practice. 



A cavalry man detects at a glance the good points of a horse ; 

 38* 



