184 



THE GARDENER'S ASSISTANT. 



on the scale by the line. The above kinds of 



level are very useful in the garden whenever any 



building operations are carried on, or in laying 



down paving, &c; and even for ground work, 



when it is of small 



extent, or when it 



is to be left to the 



execution of those 



who cannot use the 



spirit-level. 



But wherever 

 long horizontal, or 

 uniformly sloping 

 lines, are to be 

 formed, the spirit- 

 level is by far the 

 best and most expe- 

 ditious. The usual form of mounting in brass, 

 or in wood faced with brass, except over the 

 tube, is well known. They are now frequently 

 bedded in a straight-edge board, several feet in 

 length, and are thus used by builders and others. 



Fig. 217.— Level. 



Fig. 218.— Foot-level. 



A straight-edge board, say 5 or 6 feet in length, 

 4 inches broad, and 1 J inch thick, with a spirit- 

 tube bedded in the upper edge, will be found 

 very useful in gardens. For example, in making 

 walks, and having one edging level, the other 



necessary instruments, such as the theodolite, 

 &c. 



Lawn-mowers. — Since the invention of the 

 lawn-mower for the cutting of short grass, not 



Fig. 219.— Automaton Mower. 



side can be readily brought to a corresponding 

 height by levelling across. 



For taking extensive and important levels, to 

 a high degree of accuracy, an experienced sur- 

 veyor should be employed, and he provides the 



Fig. 220.— Anglo- Paris Mower. 



only is the lawn kept in better condition, but it 

 can be kept at much less cost than when the 

 scythe alone was used. Mowing-machines are 

 made of various sizes, ranging from the toy-like 

 article cutting a few inches to that of the 

 horse or motor machine cutting 30 inches. 

 The most useful size is that cutting 12 or 14 

 inches, to be directed by a man and a boy. 

 Considerable variety exists amongst lawn- 

 mowers, the majority of those used in this 

 country being what are termed gear or wheel- 

 driven. One of the best examples of these is 

 Ransome's Automaton (fig. 219). Shanks's New 

 Patent is also greatly recommended, especially 

 the horse-power. Green's lawn-mower, again, 

 is worked by a flat link chain instead 

 of the cog-wheel, and performs the 

 cutting almost without noise, which 

 is a recommendation. Green's "Silens 

 Messor " and Ransome's " Chain Auto- 

 maton" are good examples of the 

 chain-action mowers. Another useful 

 lawn-mower is the Archimedian, of 

 American invention, and so named on 

 account of its similarity to the Archi- 

 median screw. Having only two cut- 

 ting blades placed wide apart, which 

 revolve with great rapidity, it is 

 adapted for cutting long grass. Good 

 examples of this principle are William's 

 Archimedian Excelsior, Anglo -Paris 

 (fig. 220). These, it will be seen, have a central 

 handle, and the cutting cylinder, which has fewer 

 blades, is fixed to revolve more rapidly. Owing 

 to the less resistance from the fewer blades, these 

 machines are remarkably easy to work, and as 



