COMPARISON OF MANURES. 217 



Mr. Gregory thought it well for farmers to buy the raw materials 

 and do their own mixing. He had done so and knew the inside of 

 the business. The margin which had been referred to as necessary 

 was due to several causes : manufacturers have to hold their stocks 

 two years ; bags cost something ; there is much waste, and agents 

 are expensive, but we are indebted to them for stimulating farmers 

 to purchase. We ought to allow a little leeway — sa}' three or four 

 dollars per ton. "We have hardly done justice to the manufacturers 

 and dealers, but have made them the target for complaint and 

 abuse on account of failure. 



Professor Caldwell thought there was a difference of eighteen or 

 twenty per cent against mixed fertilizers as compared with the 

 raw materials, estimating the latter at cash prices. Manufacturers 

 sell on time. 



William H. Hunt was pleased with the careful statements of the 

 essay. The cost of stable manure was estimated at less than it 

 costs here ; it would be nearl}' one-half more here. He thought 

 one of the greatest advantages in using artificial fertilizers is 

 the ease with which they are applied in the growing season, when 

 farmers are too busy to put on stable manure. They can be put 

 on very rapidly. The}' have also a great advantage for remote 

 fields, the expense of applying them being so much less than that 

 of applying stable manure as often to make the practical difference 

 between planting and not planting a crop. Fertilizers can, how- 

 ever, be used to the best advantage in connection with stable 

 manures. 



Samuel Hartwell was surprised at the low value placed on hen 

 manure by Professor Caldwell. The New England Agricultural 

 Society had lately held two elaborate discussions on poultry', and 

 all considered the excrement a very valuable fertilizer ; it was 

 supposed to resemble guano. He buys horse and cow manure at 

 the same price per cord, and, considering the greater weight of 

 the latter, thinks it more valuable, cord for cord. 



Professor Caldwell said that guano is the dried and concentrated 

 dung of birds fed on fish, and is much richer in plant food than 

 the ordinary droppings from fowls fed on grain. 



Mr. Cheever asked Professor Caldwell's opinion as to the 

 economy of attempting to improve lands by ploughing in green 

 crops, either here or in New York. Can we afford to raise clover, 

 rye, and other crops for ploughing in, with the supplemental use of 



