at the Bristol Meeting in 1842. 



361 



blem remains to be solved — by how much the least force used 

 exceeds the resistance naturally and necessarily opposed to it? 

 Its solution rests Avith the machine-maker, and it will be found 

 in the application of sound mechanical principles to the structure 

 of the implement, when combined with a true knowledge of the 

 nature and amount of the several resistances to be overcome. 



The following particulars of the weight and dimensions of 

 some of the principal parts of the wheel and swing ploughs sub- 

 mitted to trial have been obligingly furnished by the makers, at 

 the request of the judges, who think that a record of them 

 may, at least, present useful matter of study to the enlightened 

 mechanic, and possibly induce him to experiment, extensively and 

 carefully, on the effects arising from any change of these pro- 

 portions as regards resistance and quality of work. He will, at 

 the same time, be naturally led to investigate the influence pro- 

 duced by the line and angle of draught, as well as by the length 

 and twist of the mouldboard, and other properties which cannot 

 be conveniently given in a table. The philosopher may medi- 

 tate on these matters, as questions of interesting research ; but 

 the mechanician alone can arrive, through observation, experi- 

 ment, and practical skill, at the construction of a perfect plough. 

 A rich harvest of fame and profit awaits his labours ; he may 

 now work in confident security that the productions of his genius 

 and industry will no longer — like the pulverizing plough — risk 

 interment and oblivion in some corner of a secluded parish ; the 

 Society offers him a fair and honourable field for the display of 

 his labours, and its hand is open to encourage, reward, and pro- 

 claim them : — 



Moveable. 



VOL. TIT. 



it Tlie cutting angle of the share is given by these two columns. 



2b 



