3* 



(icncral Woliccs. 



bciiii^ hrittU", must livst a very great length of lime. Were it not for the 

 i^reater (|iiantity of da} rc<iiiire(l, we slioulil prefer tlie tallies broader at 

 iiottoni tlum at top; beeaiise tiiey wonltl then be more eertain of standing 

 nprit.'ht, and would sink more slowly into the earth. It was thought that 

 a deviation from the shape of the common brick would procure an exem|)- 

 tion from the excise iluty ; hut Mr. Allardyce found this not to be the case. 

 A tally a foot high, formed in the upper part like that of Mr. Allardyce, 

 with nearly straight sides, but spreading out a little at the base, made of 

 Mr. Peake's terro-metallic earth (fiii. \-i.), would, we think, approach very 

 near perfection ; and would be particularly useful in an arboretum, where, 

 as at Syon, for example, the trees were allowed to attain their full age 

 and growth. — Coiul. 



Ji lidding .1 Mfichinc for cropping or s/icaring the vegetable Surface of 

 Lairiis, Grass-])/ols, c'jc. — A technical description of this machine is given 

 in the Rcpcrlori/ of Palciit Inventions, vol. x. p. 327., accompanied by an 



elevation of the left side {fig. V^.), and a ground-plan {fig. If.). The 

 machine being pushid forward, the hollow cylinder or cast-iron roller («) is 

 put in motion, and also the smaller cylinder or gage-roller (/»), the pur- 

 pose of which is, to regulate the height of the rectangidar steel plate (c). 

 The operation of shearing is performed by from four to eight spiral cutters 

 (f/), which revolve on a horizontal axis. 



In the operation of pushing forward the machine, the cylinder («) rolls 

 upon the ground like the wheel of a wheelbarrow ; and, by the wheels and 

 pinions connected with it, causes the revolving cutters (r/) to act rapitlly, by 

 their smooth outer edges, against the edge of the fixed rectangular steel j)Lite 

 (c),so as to crop or shear the grassor vegetable surface. The smaller cyhnder 

 (/;) serves etrectually to regulate the height, and to insure the steadiness of 

 the rectangular fixed cutter (c), against which the revolving cutters act. To 

 keep the smaller roller (/;) sufTiciently free from any adhering substances, 

 there is a horizontal box (<•), which serves as an axis for a thin iron scraper, 

 which is curved so as to form a portion of a cylinder, having its lower cilgc 

 bearing on the surface of the roller. 



The speed with which the machine is pushed forward when at work is 



