PROCEEDINGS OF TIIR CHEMICAL DEPARTMENT. 



219 



between the two may be at right angles to the drills. It will be 

 found convenient to stretch a string between the stakes, and to 

 let a man walk along treading on the top of the drills, so as to 

 make this line distinctly visible. 



5. It is very desirable that the plots should be made two drills 

 wide, with an intermediate space of two drills unmanured, but 

 should circumstances render it necessary, they may be made four 

 or even six drills wide. 



6. If two drills be selected as the width, measure off along 

 the drills from each stake a length of 86 feet 4 inches, and, 

 fixing stakes at these points, stretch the string between them, 

 and mark the line as before. Measure off another equal space 

 along the drills, fix stakes, and mark as before. There are thus 

 obtained two parallel spaces, between which any two drills will 

 be T | 2 of an acre. 



Should it be resolved to make the plots four drills wide, the 

 distance between the stakes must be 43 feet 2 inches ; and if 

 six drills wide, 28 feet 9 inches. 



7. The experiments are in two different series marked 1st 

 Series and 2d Series. One-half of the experimenters receive 

 the manures for the 1 st series, the other half those for the 2d. 



8. The object of the 1st series of experiments is — 1st, To com- 

 pare soluble phosphates from mineral sources, that is from 

 coprolites with those from guano ; 2d, To determine the relative 

 effects of ready formed ammonia and gelatine on the turnip ; and 

 3d, The value of potash mixed with these substances and used 

 alone. In the 2d series of experiments gelatine is omitted, and 

 Peruvian and Bolivian guanos are introduced, so as to afford a 

 point of comparison with ordinary manures as used on the farm. 



9. Each series requires in all 28 plots, if 2 nothings be intro- 

 duced, and 30 plots if (as is to be preferred) there be 4 nothings. 

 They should be arranged as in the subjoined plan, in which the 

 numbers correspond with the manures in the list, the interspaces 

 not being numbered. It is right to state that these interspaces 

 have been introduced this year in consequence of some of the 

 experimenters having found last year that the plots robbed one 

 another. 



