18 36.] 



ect, as selJom to leave any profitable result. 



When the earth which is required to be added is 

 to be found in the subsoil, then, indeed, if it be not 

 at too jrreat a depth, it may perhaps be dug, at 

 those seasons in wliich labor is cheap, at a mode- 

 rate expense; but those uistances arc rare, and the 

 charge of cartage from a distance must prevent it 

 from being undertaken by any man, although the 

 owner of the land, who is not posse^ssed of large 

 disposable capita!, or by any tenant' who cannot 

 secure the return of the outlay within the currency 

 of his lease. Composts, however, may be very 

 advantageously Ibrmed in the manner we have 

 stated — by a mixture of lime whh the earth on 

 trhich it is to be laid. 



FARMERS' REGISTER. 



243 



MIJfERAL BIAWUUES— COni/zU/w/. 



Is a compound calcareous earth found in most 

 parts of the world, and has been extensively used 

 tliroughout this kingdom, where it i.s supposed to 

 have been known to husbandmen at a very early 

 period of outr history. There are, indeed, leases 

 on record, granted in the reigns of Edward I. and 

 II-, which compel the tenants to make u.sc oi" it;t 

 but, though still employed, it has been a great de- 

 gree superseded by the more recent introduction of 

 Ij.rae, of the properties of which it in some mea- 

 sure partakes. The term denoting it was former- 

 ly used in a very vague sense, for it is a substance 

 consisting ol' various materials, and it has conse- 

 quently happened, that what has been supposed 

 to apply to one species, did not hold good when 

 afiirmed of another. Although principally deem- 

 ed valuable on account of the calcareous matter 

 which it usually contains, still its composition dif- 

 fers so essentially, that its influence as manure is 

 but imperlectly understood; yet theoretic writings 

 abound in general directions for its use, Avhich are 

 frequently found not to answer in practice, i'or their 

 rules are drawn either from statements which 

 liave been made of the effect of its application on 

 particular soils, or from analyses of its qualities, 

 which, as these vary in innumerable instances, 

 frequently lead farmers astray. lis real value can, 

 therefore, be only ascertained throun-h the pracii- 

 cal experience of those who have cither actually 

 tried its clHcacy, or who have witnessed it in their 

 own neighborhood. 



This ignorance of the distinguishing properties 

 of marl has necessarily led to many mistakes in 



t The Charta Forestce, passed in 1223, mentions the 

 right of sinking marl-pits; and Dailies Barrington gives 

 a quotation from Pliny (lib. xvii. c. vi.,) in Avhich he 

 mentions a substance used in Britain and France as ma- 

 nure, called marga, which he conceives is a mistake for 

 marla. And in the Statutum Wallicc, 12 Edw. 

 I., the sheriff and coroner are directed to inquire as to 

 marl-pits adjoining public roads, s'.iowing its then com- 

 mon use. The uses of marl and lime are indeed men- 

 tioned in a treatise on rural economy written in the 

 Welsh language, and supposed to be from three to four 

 hundred years old; of which a translation has been 

 given by Mr. Davi-, in his Survey of South Wales. It 

 contains mmj'- curious and valuable remarks, which 

 show that ignorance on the subject of agriculture did 

 not prevail at that timi to the extent which is generel- 

 })' imagined. 



its application, which have occasioned the variety 

 of opinions that are entertained regarding its use. 

 In most jilaces where it was anciently emjjloyed, 

 and where its fertilizing influence was discovered 

 to be eminently great, it was thought by many 

 liirmers that it could be made to supersede" the use 

 of dung; they, therefore, in many mstances, sold 

 tiieir hay and straw, and although, notwithstand- 

 ing this reduction of the quantity of putrescent 

 manure, they still tor a time obtained large crops, 

 yet, eventually, the chemical effects of the marl 

 exhausted the land. No second mariing could 

 operate upon it until it had been renovated by re- 

 peated applications of dung; and thus has arisen 

 the old saying, cited by Eurnaby Googe, who 

 wrote so long ago as the middle of the sixteenth 

 centur\', that Hhne and marl arc good for the father, 

 but bad for the soj?.' In this manner, also, some 

 valuable discoveries in agriculture have fallen into 

 disuse through their mistaken application, when 

 governed by local circumstances which were ill 

 understood; wdierever marl of a kind adapted to 

 the soil has been applied, and that a judicious sys- 

 tem of culture has been pursued, without either 

 over-cropping, or neglecting the use of putrescent 

 manure, the proverb is so far from being well 

 founded, that the contrary may be safely affirm- 

 ed. 



The common dcjinition of marl given us by the 

 bcot writers on fossils, is — thqit it is composed ot' 

 clay, sand, and lime, very intimately, but une- 

 qually mixed, slightly coherent, not ductile, but 

 stiff, or viscid, when moist; most easily difl'usible 

 in, and disunited by, water, or even by exposure 

 to the air, and by it reduced to a soft, loose, incohe- 

 sivc mass — for the most part composed of nothing 

 more than calcareous earth — in which its chief 

 value consists — combmed with a Utile mineral oil, 

 clay, and sonsetimcs with ochre, or iron. It is 

 also generally considered as a characteristic of 

 mad, that it effervesces with acids, though to that 

 various exceptions have been discovered-, from 

 which it has been supposed that, when deprived 

 of that test, it contains no calcareous matter, yet 

 it is found to produce ameliorating effects upon 

 the soil.* Notwithstanding this summary descrip- 

 tion, its appearance is, however, as varied as its 

 properties, being of color nearly pure wdiite, to the 

 darkest shades of brown and red, interveined with 

 blue and yellow. It also exists in different kinds 

 of land, is seldom found as a stratum of much 

 length, but generally in detached masses at va- 

 rious depths, sometimes in wide and dense per- 

 pendicular layers, at others in streaks, running in 

 lines parallel witli the horizon, or again intersect- 

 ing each other at right angles, usually resting on 

 sand or gravel, and is classed, according to its 

 qualities, into the following distinct species. 



}.' Clayey marl, which improves sandy land, 

 and seems to act as clay in changing the nature^ 

 of the soil. In land consisting of a mixture of 

 sand and loam, or of sand and gravel, then, the 



* A bluish marl much used in some parts of Ireland, 

 and long celebrated as a manure, makes no ebullition 

 with acids; neither do seveial of the red marls; yet 

 many of them are known to be productive of great 

 improvement to land. See Dr. Rutty's Essay on the 

 Natural History of Dublin, appended to the SiuTcy of 

 the County; and also Holland's Survey of Cheshire, 

 noJe, p. 225. 



