282 
STATE AGRICULTUKAL SOCIETY. 
A plankroad is a good road when in proper condition, and 
may be a necessary kind in some districts of the country; 
hence it may be well to state that it is claimed that, by steam¬ 
ing the plank, and charging them with creosote, costing about 
eight dollars per thousand feet, board measure, their durability 
will be doubled. 
THE LONGITUDINAL GRADE FOR A ROAD. 
There is perhapse no branch of the subject under considera¬ 
tion which demands more attention by the engineer than that 
of the reduction of road grades to the minimum under all 
practicable circumstances. We can better afford to increase the 
length of a road considerably than to retain grades, in places, 
so heavy that a team is unable to haul more than half, or per¬ 
haps one-quarter, the load it can on all the remainder of it. 
Eoads which are steep in the line of their axes are not only 
more severe on teams, but they are dangerous, and much more 
expensive to keep in repair. Various opinions have been ex¬ 
pressed by engineers and essayists on this cubject. Mr. H. F. 
French of Boston, Massachusetts, in a .very able paper on 
roads, contained in the report of this department for 1866, 
says : “ In view of every consideration, except drainage, the 
level line is probably the best; but, as drainage is essential, 
and, as will be seen when we come to consider the construction 
of roads, it is desirable to make them as flat as possibly trans- 
versley, a slight slope in the length of them is found expedient. 
This slope should be one in two hundred, which is sufficient 
for drainage without injury by washing, and adds little to the 
draught.” 
A grade of one in two hundred is a very desirable one, so 
far as draught is concerned, but it is nearer level than is prac¬ 
ticable on any considerable proportion of our country roads; 
and, as regards drainage, it will be of little service. Much 
lateral slope is objectionable, but we do not consider that a 
slope of one-quarter of an inch to one foot is so, while it is 
sufficient to provide lateral drainage, which is more efficient 
