NEW BOOKS. 319 



^f the subjects treated of, the whole range and scope of the lec- 

 I tures as they were delivered. 



"Tlie first part is devoted to the organic elements and parts of plants, the nature and 

 sources of those elements, and to an explanation of the mode in which they become con- 

 verted into the substance of plants ; the second to the inorganic elements of plants, com- 

 prehending the study of tlie soils from which these elements are derived, and the general re- 

 lations of geology to agriculture ; the third to the various methods, mechanical and chemi- 

 cal, by which tiie soil may be improved, and especially to the nature of manures by which 

 soils are made more productive ; and the fourth to the results of vegetation, to the kind and 

 value of the food produced under different circumstances, and its relation to the growth 

 and feeding of cattle, and to the amount and quality of dairy produce^" 



It will be perceived that this synopsis of subjects covers a wide 

 jrange of matter ; in fact, the whole field of domestic economy, 

 jThat the reader may have some idea how the distinguished lecturer 

 .handles his subjects, we give one extract at random. 



" Why Lijie must be kept near the surface. — Nor will you fail to see the important 

 reasons why lime ought to be kept near the surface of the soil — since 



1st. The action of hme on organic matter is almost nothing in the absence of air and 

 jmoisture. If the lime sink, therefore, beyond the constant reach of fresh air, its efficacy 

 lis in a great degree lost, 



. 2d. But the agency of the light and heat of the sun, though I have not hitherto spedally 

 'insisted upon their action, are scarcely less necessary to the full experience of the benefits 

 which lime is capable of conferring. The light of the sun accelerates nearly all the che- 

 (mical decompositions that take place in the soil — while some it appears especially to pro- 

 imote. The warmth of the sun's rays may penetrate to some depth, but the light can 

 'only act upon the immediate surface of the soil. Hence the skill ul agriculturist will en- 

 deavor, if possible, to keep some of his lime at least upon the very surface of his arable 

 land. Perhaps this influence of light might be even adduced as an argument in favor of 

 the frequent application of lime in small doses, as a means of keeping a portion of it al- 

 ways within reach of the sun's rays ; and this more especially on grass lands, to which no 

 mechanical means can be applied for the purpose of bringing again to the surface the Erne 

 that has sunk. 



There are, at the same time, as you will recollect, good reasons, also, why a portion of 

 ihe lime should be diffused through the soil, both for the purpose of combining with or- 

 ganic acids already existing there, and with a view of acting upon certain inorganic or 

 mineral substances, which are either decidedly injurious, or by the action of hme may be 

 rendered more wholesome to vegetation- 



In order that this diffusion may be effected, and especially that lime may not be unnecessarily 

 wasted where pains are taken by mechanical means to keep it near the surface, an efficient 

 isystem o; underdrainage should be carefully kept up. Where rains that fall are allowed to 

 (flow off the surface of the land, they wash more lime away ihe more carefully it is kept 

 jamong the upper soil — but where a free outlet is affurded to the waters beneath, ihey 

 carry the hme with them as they sink towards the subsoil, and have been robbed again of 

 pe greater part of it before they escape into the drains. Thus, on drained land, the rains 

 Ithat fall aid lime in producing its beneficial effects, while in undrained land they in a 

 greater or less degree counteract it." 



