ESCULENT -EOOTED PLANTS.— THE POTATO. 



211 



and reach to within 2 inches of the drill, by 

 which the seed can be sown even in windy wea- 

 ther, when it could not be safely done by hand. 

 The lower ends of the tubes are also sloped off. 



by which the seeds are readily seen as they fall. 

 A set of similar coulters is placed behind the 

 cross arm or bar, but somewhat wider than 

 those in front, and reversed in their position, so 



Fig. 92. 



DRILLING AND 60WIN0 MACHINII. 



that as the seed is dropped in the drill, and the 

 machine in motion, these latter cover the seed 

 by drawing the soil, pushed aside by the open- 

 ing coulters, over the seed, which finishes the 

 operation. 



The quantity of seed delivered is regulated 

 by the extent of opening in the delivering-tubes, 

 which can be graduated to any extent to suit 

 such seeds as onions, turnips, &c.; and can 

 be entirely stopped at the ends of the rows, 

 by the boy who guides the machine behind 

 simply raising the iron rod shown between 

 the stilts. 



In commencing the operation of drilling and 

 sowing, a Une is stretched from one end of the 

 ground to the other : along this line either the 

 right-hand wheel, or the right-hand drill-coulter, 

 according to circumstances, is to travel, so that 

 the drills may be set oif straight at starting. 

 The machine is drawn along to the other end 

 of the ground by the man, while the boy guides 

 it along the line — thus opening, sowing, and 

 covering in at once the number of drills the 

 machine is set to. When the first series of 

 drills is finished, the machine is turned, and 

 proceeds in like manner to the other end of the 

 ground, performing the same operation, the boy 

 keeping in this case the left-hand wheel exactly 

 upon the previous wheel-track. By this means, 

 we believe, 2 acres of onions or turnips could 

 be sown per day. Like all sowing-machines, 

 this is best adapted for what are known as 

 round seeds, such as rape, turnip, cabbage, 

 onions, &c.; but it is also adapted for sowing 

 parsnips, carrots, &c., provided the seeds of the 

 latter are properly rubbed down and mixed 

 with sand, as is usually done. The mould- 

 boards being attached, deep drills can be drawn 

 for potatoes; and when one of these is removed, 

 short dung or any of the artificial manures can be 

 ploughed in, or the weeds on the surface buried 

 as in ordinary digging, and in one-third of the 

 time. All such machines are, however, better 



adapted to light soils, or to ground in a high 

 state of cultivation. 



The later or principal crops should not 

 be earthed up at all — or, if so, only to a 

 limited extent ; and for this purpose our 

 improved cultivator with double mould- 

 boards will be found far better than the 

 ordinary hoe earthing-up system. If 

 potatoes are planted 6 inches deep, they 

 are rather injured than impi'oved by 

 earthing up, some say to the extent of 

 diminishing the crop one-fourth. We 

 have remarked in the article Carrot, p. 

 178, that deep-hoeing between the rows 

 is inexpedient, as it has the effect of en- 

 couraging the lateral fibres to extend, and 

 to induce greater growth in them, produc- 

 ing side roots, or what are commonly called 

 forks. Now, the very opposite course 

 should be pursued in the case of the po- 

 tato, and every encouragement given to 

 the side roots to extend themselves, for 

 nearly at their extremities the tubers are 

 formed; so that deeply stirring the ground 

 between them tends to their extension. 

 This process, however, must not be car- 

 ried beyond a certain stage in the growth 

 of the plants, else the extremities of the 

 roots, which it is our object to encourage, 

 may become seriously injured if deep- 

 stirring takes place after they have nearly 

 met in the spaces between the rows. This 

 can only be ascertained upon examina- 

 tion. Some kinds of potatoes produce 

 their tubers, at a much greater distance 



