CALCARKOUS MANURES— CONTENTS. 315 



Clover and gypsum, 113. Farm-yard manure, 113, Leaves, 114 Causes of results in practice on a 

 large scnle failiiis short of proper and available effects, ]ir> Value of sandy soils, 116. 'J'lie thinness 

 of soils more ohjcciionable than sandiness or barrenness, 117. Itate of increase from mailing on soils 

 of different kinds, 117. 



Chapter XII.— The. permanency of calcareous manures, and of alimentanj or pu- 

 trescent manures when combined with the calcareous. 



The effects of calcareous manures permanent, 118- Pi'asons for such effect, 119. TTsual transient ope- 

 ralion of putrescent manuies, IISJ— become permanent on niaikd land, 119 Illustrations of such sup- 

 posed operation, 120. 8tatemeiits in proof, 121. The future and continued effects of calcareous 

 manures supposed from the mode ol action, 122. 



Chapter XIII. — Tlic expense and profit of marling. 



Mistaken views of the value of marling, and false mode of estimating profits of improvements, 124; 

 True value of land, and of permanent improvements of its productiveness, 125. Mode of estimating 

 the expenses of marling, 12S. Water carriage ot marl, 130. On canals and i ail roads, 131. 



Chapter XI K — Estimates of the cost (f labor applied to marling. 



Proper grounds for estimates of cost, 131. Cost of the labor of a uearo man, 132. Woman, girl and 

 boy, 133. Horse or mule, 133. Amount of labor of several large jobs of marling 134 to 140. 



Cha^Aer XV. — The vse of calcareous earth recommended to preserve putrescent 

 manures, and to promote cleanliness and health. 



Effects of calcareous earth preventing \va^:te of products of putrefying animal matter, 140. Cases in 

 which this power might be usefully employed. 141. In towns, for cleanliness and health, 142. Unfit- 

 ness of quick lime for the same ends, 143. Different actions of quick and mild liine on putrescent 

 matters, 144. Supposed and also known particular results to health, from use ol marl, 144. I'roofa 

 adduced in the paving with shells of the city of Mobile, 145 ; from the burning of towns 146 ; from the 

 calcareous pr.iiiie region of Alabama, 147. E.\tensive changes from former sickliness already pro- 

 duced by marling', 147. Confirmation of this doctrine, by facts in France, 149. 



Chapter XVI. — Directions for the mechanical operations of applying marl as 



raanure. 



The marls of lower Virginia, 150 ; comparative value of different bodies, 152. Directions for analyzing, 

 by solution and precipitation 1.52. Necessity for thus testing the value of marls, 154. Searching for 

 concealed marl by use of the auger, 154. Deep lying marl, and suggestions for extracting it, 155. 

 Descriptions and advantages of crane for drawing up marl from pits, 155. Excavation of marl beds, 

 157. Hemoval of overlying earth, 153 Draining and working of a wet pit, 159, Making roads up 

 hills, 160. The proper utensils for working in marl, 101. Carts, teams, and laborers, 161, Common 

 error in unequal spreading of marl, 161. 



Chapter XI II. — The progress of marling in Virginia. 



Obstacles to the progress of all new improvements in agriculture, 162. The beginning and proiress of 

 marling, and present general state of in Virginia, 162. Progrcis and effects of liming 103." Stone 

 lime, 166. 



PART THIRD— APPENDIX. 



Introductory remarks -..-.-.....ig7 



JVoie /. — Proofs of the existence of acid soils furnished by the recent researches 



if chemists. 



Berzelius' work^ on chemistry, 167. Products of putrefaction of vegetable matters, 168. Mould or 

 Aumjis, 168. E.vtract of mould, 169. Gcine (or liuiiiin) and geie or humic acid, 170. Carbonaceous 

 mould, 172, Soil, 172. Acid soils, 174. 



^ote II. — jldditional proof offered, by the production and existence of black wa- 

 jiers, of the action of tunc ia combining vei^elable matters with soil. 



Biack 01 dark colors of waters of certain streams and mill ponds, and absence of coloring matter in 

 others, 175. Cause of the different circainstances, the absence or presence of lime in the soils, 176. 

 Proof and illustrations 176. Transparency of lime stone waters. 177. The combination of coloring 

 vegetable matter with the soil, the natural process of fertilization J78. 



