[60] 



of air than the jun£lion of the tube fig. 4, to the 

 neck e e, in fig. 2. 



N. B. e e \s a neck of woo.d making a part of 

 the bottom fig. 2, whereon to fccure the lube fig. 4, 

 when applied to the nolle. 



The joints of the pipes, when put together for ufe, 

 fliould be made air-tight by means of bees-wax or 

 fome fi:ronger cement, till they reach the bottom of 

 the veflfel, when there is no farther need of this pre- 

 caution. 



The horizontal pipes fliould run by the fide of 

 the kelfon the whole length of the hold, the tin 

 plates of which K. is made, fliould be punched in 

 holes like the rofe of a watering-pot, in two or three 

 lines only at mofl:, and then formed into a tube with 

 the rough fide outwards. L. may have four or five 

 lines of the like perforations. M. and the reft fliould 

 gradually increafe in their number as they advance 

 towards the middle of the hold, and continue fully 

 perforated to the laft pipe, which fliould be clofed 

 at its end to prevent the ingrefs of the corn. 



It is the centre of the cargo which raoft require? 

 ventilating, yet air fliould pervade the whole. Like 

 the trade-winds, it will dire£t its courfe to the part 

 mofl heated, and having effefted its falutary purpofe 

 there, will difperle itfelf to refrcfli the mafs. 



Where the hatches are clofe corked to prevent 

 the influx of water, vent-holes may be bored in con* 



venient 



