190 EXPERIMENT STATION. [Jan. 



ments with lettuce the difference in the percentage of 

 germination and growth of seedlings in ashes was determined 

 by differences in the air supply furnished by the various 

 grades of particles employed. 



Textuke of Massachusetts Soils. 



Eor some years this department has made mechanical 

 analyses of soils in connection with the study of problems 

 relating to greenhouse crops, and for various persons who 

 desire to know the constituents of some particular soil. A list 

 including some of the analyses is presented with this report, 

 the soils being grouped in a general way under different 

 headings. 



In the list of soils which follows, acknowledgment should 

 be made to those who have taken part in this work, most of 

 whom have been from time to time students and assistants in 

 our laboratory. Some of these soils were analyzed by Mr. 

 Asa S. Kinney, now director of the Botanical Gardens at 

 Mount Holyoke College; others by Messrs. A. A. Harmon, 

 A. C. Monahan, A. L. Dacy, E. H. Scott, L. K. Liang; and 

 particularly Mr. N. F. Monahan, assistant in the laboratory, 

 who has made by far the greatest number of these analyses. 



The methods employed are those recommended by Dr. 

 Milton Whitney. In some of the earlier samples the finer- 

 grade material was separated by the gravity method, while 

 all the later analyses have been made by the centrifugal 

 method of separation. In all cases 20 grams of soil were 

 used in each analysis. 



The soils best adapted to general market gardening are 

 those which contain considerable proportions of coarse ma- 

 terial, which render them loose and friable. Such soils pre- 

 dominate near the coast, and excellent types may be found in 

 many of our river valleys. The soils about Boston, especially 

 those in Arlington, Belmont, Newton, Bedford and Concord, 

 are exceptionally well adapted to market-gardening purposes, 

 and some of the best crops in the United States are raised in 

 these towns. Market gardening has been carried on in the 

 above-named localities for many years, and renuirkable skill 

 has been developed in handling certain crops. This statement 



