500 Transactions of the American Institute. 



apparatus consists of a glass bottle and tube, connected by a piece of 

 rubber tubing. The glass tube is closed by a cork at one end, and is 

 marked off in eighth or quarter inches. It is known that the physi- 

 cal properties of the soil (by "physical properties" is meant the 

 relation of the soil to the atmospherical agents), its consistency, its 

 diminution of bulk on drying, its ability to retain and absorb heat,, 

 etc., depend largely upon the per centage of coarse and fine sand, and 

 of clayey and humus substances. It has been found that 6.5 cubic 

 centimeters of coarse sand weigh ten grammes ; 8.5 cubic centimeters 

 fine sand weigh also ten grammes. To separate, take ten grammes 

 dry soil, sieve it, mix with some water in a saucer, boil for 

 twenty or thirty minutes if of sandy, forty minutes to one hour 

 if of clayey nature, stirring occasionally. Let the whole cool down, 

 pour it into the bottle, clean the saucer, taking care that all the 

 particles of soil come into this bottle ; adjust the tube, shake it a 

 few minutes, then let the mass settle in the tube. The coarse sand, 

 having the greatest specific gravity, will settle first, upon it the fine 

 sand, and at last the clayey and humus portions of the soil. The 

 cubic centimeters of coarse and fine sand are multiplied with the 

 above gifen figures, and the weight once found, the per centage is 

 quickly calculated. There are other apparatus that will work more 

 accurately, but they are complicated and dear, and cannot be made 

 without the help of skillful mechanics. 



Prof. Henry E. Colton — It may be worth while to explain that a 

 cubic centimeter of water weighs one gramme ; one gramme is 15.433 

 troy ounces. A centimeter in length is nearly 394-1, OOOths of an 

 inch. 



Mr. Henry Stewart — Our forefathers had a way, and I believe the 

 plan is still adhered to, of making similar but perhaps less exact 

 tests, by putting some soil in a bottle of water, shaking it well, and 

 leaving the ingredients of different density to arrange themselves in 

 their proper order. 



Potatoes. 



A correspondent, Poultney, Vt., asked what kind of manure, next 

 to stable, is best for the Early Rose potato ; and is black loam, twelve 

 inches deep, with an underlayer of clay, suitable soil for this crop ? 



Dr. F. M. Hexamer replied — The best manure for Early Rose and 

 all other potatoes is well decomposed stable manure. Wood ashes 

 are a special manure for potatoes ; bone-dust is nearly as valuable, and 

 on heavy land muck is an excellent fertilizer. A black loam with. 



