136 MASSACHUSETTS AGRICULTURE. 



Peruvians as far back as their history extends, "was not com- 

 mercially introduced into England till 1840. So of crushed 

 bones, and many of the artificial specifics, used as manures ; 

 some of them, being called composts, were not known until a 

 recent period. 



Having thus briefly sketched the history of the subject un- 

 der consideration, it is time to proceed directly to its discus- 

 sion. 



Manure is defined by Dr. Lieber, the author of a German 

 Lexicon, to be "vegetable, animal, and mineral matters, intro- 

 duced into the soil to accelerate vegetation and increase the 

 production of crops." Loudon, in his work on Agriculture, 

 says, "Every species of matter capable of promoting the 

 growth of vegetables may be considered as manure." Profess- 

 or Low, in his Elements of Agriculture, says, "All substances 

 which, when mixed with the matter of the soil, tend to fertilize 

 it, are in common language manures." Mr. Johnson, in his 

 Farmers' Encyclopedia, says a manure may be defined to be 

 any fertilizing element, whether a compound or simple ingre- 

 dient, if added to a soil of which it is naturally deficient. In 

 these definitions, Professor Licbig and Dr. Dana, two modern 

 writers on manurial specifics, agree. 



Professor Low classifies manures as follows: 1. Animal and 

 vegetable manures ; 2. Mineral manures ; 3. Mixed manures. 



They are also classified into organic, inorganic, and mixed ; 

 into animal, vegetable, and mineral; nitrogenous, carbonace- 

 ous, saline, and earthy ; general and special ; natural and arti- 

 ficial ; simple and compound ; massive, powdery, and liquid ; 

 diffused and concentrated; volatile and fixed ; ephemeral and 

 permanent ; chemical and mechanical ; top dressings, and incor- 

 porated and buried manures ; into such as contain the prepared 

 food for plants, and such as resolve themselves by decomposi- 

 tion into the food of plants ; such as partly or wholly combine 

 with ingredients in the soil, or the atmosphere, to form the 

 food of plants ; such as absorb and store up their food from 

 the atmosphere; such as eliminate their food from the soil; 

 such as increase the absorption and nutrition of plants by stim- 

 ulating or strengthening their organism; such as increase their 

 absorption and nutrition by improving the mechanical condi- 



