AND THE BLOWING AWAY OF SANDS BY WIND. 165 



The effect in practice is most striking. Fields and farms, winch 

 before were noted for the dense and enormous clouds of dust pass- 

 ing away from them in every high and drying wind, become free 

 from such loss in a short time after being marled or well limed.*J 



The effect of marling will be much lessened by the soil being 

 kept under exhausting cultivation. Such were the circumstances 

 under which we may suppose that marl was tried and abandoned 

 many years ago, in the case referred to in page 114. Proceeding 

 upon the false supposition that marl was to enrich by direct action, 

 like dung, it is most probable that it was applied to some of the 

 poorest and most exhausted land, for the purpose of giving the 

 manure wliat is called a " fair trial." The disappointment of such 

 ill-founded expectations was a sufficient reason for the experiment 

 not being repeated, or being scarcely ever referred to again, unless 

 as evidence of the worthlessness of marl. Yet with proper views 

 of the action of this manure, this experiment might at first have 

 as well proved the early efficacy and value of marl, as it now does 

 its dur ability. f 



When acid lands are equally poor, the increase of the first crop 

 from marling will be greater on sandy, than on clay soils ; though 

 the latter, by heavier dressings and longer time, may ultimately 



* I have heard (but do not know from my own personal observation), 

 that the well-known and valuable farm of Lower Wyanokc, the*property of 

 the late Fielding Lewis, presented a remarkable example of the frequent 

 loss of soil by winds, before the liming, and of the cessation afterwards. 



On March 1st, 1850, a few days before the writing of these lines, I saw 

 from the eminence on which my present dwelling stands, a very remarka- 

 ble exhibition of this conservative power of marl. The night before, there 

 had fallen a heavy shower ; and also some drizzle after day-break, suc- 

 ceeded by bright sunshine and a furious wind. Though the rain-water had 

 stood in puddles in the ruts and low spots of hard roads in the morning, 

 by 11 o'clock, A. M., dense clouds of dust, rising as high as the tops of the 

 forest trees on the higher lands, were seen driven off from the light fields 

 of three different and detached neighbouring farms, and which had not been 

 marled. A much broader space of surface, intermediate or adjoining, was 

 also in view, much of which was equally sandy, arid fully as much exposed 

 to the wind. All this land (except one small field, which was both stiff, and 

 low-lying, and of course not then dry) had been well marled ; and from 

 none of it was any dust seen to rise. Of the several thousand acres of 

 arable land in sight, and mostly of sandy soil, all the farms and fields not 

 marled (and not of clay or wet soil) might have been designated by the 

 clouds of dust then rising and passing off from them. 



f- Confirmation. "One thing, however, must be borne in mind by those 

 who, in adopting the best system of [successive] liming, do not wish both 

 to injure their land and to meet with ultimate disappointment. Organic 

 matter in the form of farm-yard manure, or green crops ploughed under, 

 &c. &c., must be abundantly and systematically added, if at the end of 20 

 or 40 years the land in which the full supply of lime is kept up is to retain 

 its original fertility. . . . Otherwise present fertility and gain will be 

 followed by future barrenness and loss." Johnston's Lectures, p. 386. 



