On the New Jersey Marls, 



by-place and afterward observing the astonishing growth 

 of vegetables around the spot. Trees that grow on land 

 that has marl within a few feet of its surface, when blown 

 up have their roots flat at the bottom, they not entering 

 the marl ; for we dont find the roots of any vegetable in 

 marl of a strong kind as it lies in its natural bed ; proba- 

 bly it requires an exposure to the atmosphere to fit it for 

 promoting vegetation ; and it is also remarkable that no 

 worm or reptile whatever is ever found in marl. The 

 water which runs from many species of marl, particularly 

 the gunpowder and the black hard kinds, are strongly 

 impregnated with iron, leaving a tinge of that metal on 

 whatever it runs over. All the marls, after a few days 

 exposure to the air in dry weather, have a white frosty 

 appearance on the surface, some of which has an allumi- 

 nous taste, others not so. The depth or thickness of the 

 strata of marl at present is not much known, there having 

 been but few instances of going through it. Some of the 

 marl lies very compact, and too hard to split up with the 

 spade ; others more loose, particularly the gunpowder 

 kind, which will split up very readily ; and after getting 

 down into the springs the marl will run into the pit like 

 quicksand. At some places the upper surface of the 

 marl is nearly level for some distance, the inequalities of 

 the ground being occasioned by a greater quantity of 

 earth brought on it ; while we find other instances of the 

 marl rising and falling with the surface of the ground, so 

 as to have very much an uniform thickness of earth on it ; 

 but there are large meadows of several hundred acres to- 

 gether in which the marl is only covered with a soil from 

 six to eighteen inches, and with an iron ore called iron 

 stone, from a few inches to two feet thick ; and where 

 the marl lies near the surface in wet situations, there is 

 generally an iron-stone crust on it, particularly on the gun- 

 powder and the hard marl kinds. The water which runs 



