( 22 ) 



doubt operate as powerfully here, if properly ap- 

 plied *, 



Woollen 



* The marl which has been difcovered upon the Boughton eftate, was found in a 

 low, and, rather wet fituation in Boughton-park, at about 20 inches from the fur- 

 face, which confifls of a dark rich loamy foil ; a white loamy earth prefents itfelf, mix- 

 ed with a great quantity of fine fmall flielly fubftances, which, when perfedlly drained 

 and dried, either by the fun or fire, adheres together in lumps, and becomes extremely 

 light. Upon immerging a piece of it in common vinegar, it caufes a great effervefcence. 

 The flielly particles in a great meafure diffolve, and the whole foon becomes a fmooth 

 liquid pliiller. This ftratum of white earth is from 12 to 18 inches in thicknefs, when 

 another ftratum is found, confifting of a darker coloured earth, with a large mixture of 

 blue clay, and a much fmaller quantity of fliells than the white kind. This laft ftra- 

 tum continues about the fame depth as the former, when the ftrong clay makes its ap- 

 pearance The following valuable information, refpefting this marl, has been given by 



an injenious and learned chvmift in Scotland. 



" I have affayed the two marls ; one of them is almofl; white and chalky ; the other, of a 

 " yellowifli colour, and darker, and more plaftic, like clay. The firft is as rich a marl 

 *' as ever I affayed. It is, when perfeftly dry, very nearly equal in value to the firft chalk, 

 " or beft limeftones ; the difference is not more than 2 or 3 per ce?tt. ; and it has the ad- 

 " vantage, as a manure, of not needing to be burnt. But when newly taken up from 

 " its bed, it muft contain 'a confiderable quantity of water, and its value will be the 

 " lefs by this quantity of water, whatever it is. If, for example, one ton weight of 

 "■ the wet marl contains a quarter of a ton of water, it will be equal in value to three- 

 " fourths of a ton nearly of the beft unburnt limeftone. The quantity of water is 

 " eafily learned, -by weighing a quantity of the wet marl, and then drying it tho- 

 " roughly, and laftly weighing it again. 



" The yellowiili and more clayifti marl is of little value in comparifon with the form- 

 " er. It contains only when perfedlly dry, one part of calcareous or lime earth in ten 

 •' of marl ; the nine parts being clay and fand. Marls, however, not richer than this, 

 " are valuable in fome places that are at a diftance from lime, and in ufing them, a 

 " greater quantity is laid on the foil, to make up for their defedl; in quality." 



From the above chymical experiment, it appears, that the white earth contains a much 

 larger proportion of calcareous matter, than the darker coloured. There cannot be the 

 fmalleft doubt of both proving a very valuable manure, particularly for grafs-ground ; 

 but a much fmaller quantity will be required for that purpofe, of the former, than of the 

 latter. It is prefumcd a confiderable quantity of this marl might be found in the neigh- 

 bourhood, but chiefly in low aud moift fituations. The fame ftratas of earth here men- 

 tioned having been found, by digging in many other places, near to which this has been 

 difcovered. White earth of the fame kind, has been found at the bottom of a pond in a 

 low wet part of the park, at the diftance of near3C0 yards from the firft fituation, from 



which 



