Premiums proposed hy the Xxxvil 



ing already well known. But clays, marles, g^-psum and 

 sand, or other natural substances, fall within the meaning of 

 this proposal. The crops, so far as consistent with good 

 husbandr)^, to be the same after improvement as before, and 

 their relative product to be given. All auxiliarj', and influ- 

 encing circumstances to be mentioned ; as well as the mode 

 and results ol the analysis ; and the proportions of the com- 

 binations. Artificial manures, after improvement, (lime at 

 this stage mav be one) may be used, if the like had been be- 

 fore applied : and all the means and circumstances are to be 

 fairly developed. A piece of plate of the value of one hun- 

 dred dollars. 



The object is, not only to promote experiments calculated 

 to improve farms, out of the materials found upon them ; 

 and thus save, or extend the efficacy of artificial manures; 

 but to excite a spirit of exploration for fossils, earths, marie, 

 and clays, applicable to agricultural as well as manufacturing 

 purposes. For subterraneous researches, the society have 

 provided a very complete set of boring instruments, with 

 which those who will use them effectually, may be accom- 

 modated. 



2. Trench Ploughing. 



For the greatest quantity and best trench ploughed worn 

 land, not less than five acres. The trenching not less than 

 ten inches deep. 



The following mode of trenching is recommended, as be- 

 ing kno^vn to be practicable, and easily performed. 



1. Provide a light plough, from 12 to 15 inches wide in 

 the hind part of the span or sole, calculated to pare off the 

 sod from 2 to 3 inches deep, according to the depths of the 

 roots of weeds. 



2. A strong heavy Trench Plough^ capable of turning a 

 depth of from 8 to 10 inches of mould, or earth. This must 

 be one or two inches narrower than the Paring Plough^ or 

 it will cut into the unpared sod. The first is to be drawn by 



