to the Cttltivation of the Land. 
209 
poses for which an 8-hovse power wonld be sufficient, is an engine built with 
tVanie, water-t^xnlv, reversing gear link-motion, travelling-wheels 12 inches 
wide, and made locomotive with the pitch-chain, for ; or if with my 
patent balanced boiler, &c., 360/. The 10-horso engine [described above] 
costs 4:201." 
There is a simple method of overcoming the difficulty of a 
varying level of the boiler, namely, preventing " priming," in 
spite of a considerable depth of water above the fire-box, by 
taking the steam from the top of a very high steam-dome. Mr. 
Collinson Hall and Mr. Tliomas Charlton patented in I\[ay, 1857, 
the engine of peculiar construction, worked at enormously high 
pressure, which appeared at the Salisbury Meeting ; and they 
divide the steam-pipe, so as to take the steam from two domes, 
or from either at pleasure, so as always to get " dry " steam from 
the highest point, no matter what may be the position of the 
boiler. This engine is fitted with the Boydell rails, and was em- 
ployed to drag implements behind, or propel them before, or at 
one side of it ; but Mr. Hall has now adopted wire-rope culture, 
finding his engine answer every requirement as a locomotive 
along fields and common roads. 
Locomotives are also being made for running at a rapid rate 
upon ordinary roads. A correspondent writes from Trentham, 
Staffordshire, January 25, 1859 : — 
" I have been working a little engine lately, made to carry three people 
(besides stoker beliind) : the machinery is under a ton, hut with water and 
passengers, amounts to near 30 cwt. I have driven it 1 mile in 5 minutes, 
and 1 mile in 6 minutes average, for the hour together between here and 
Wolverton. Last week I drove it from Trentham to Lillcshall, in Shropshire, 
26 miles, before 11 o'clock a.m. ; consum])tion of coal 6 to 7 lbs. per mile. It 
requires a light engine, worked at a high pressure ; with only 10 per cent, more 
weight we could not get up the hills. The great objection now is the danger 
of frightening horses ; but I have nm this little one upwards of 100 miles, and 
a 7-horse engine as many, without any accident, a«d believe horses would soon 
get accustomed to them if introduced." 
There are several other locomotive portable engines, which I 
have not time now to describe: as that of Mr. Lee of Walsall, 
shown at the Salisbury Meeting, having Boydell rails attached, and 
propelling itself by a pinion on the crank-shaft gearing, with a 
spur-wheel fixed to one of the travelling wheels ; that again 
which Mr. William Cambridge, of Market Lavington, Wilts, 
exhibited on the same occasion, made self-propelling by pinions 
and spur-wheels, driving its main carriage-wheels. 
Mr. William Bray, of Folkestone, patented a traction-engine 
in December, 1856, in which blades are made to protrude radi- 
ally from the periphery of the travelling-wheel to any extent 
required, and slide in and out by means of a fixed eccentric, so as 
VOL. XX, P 
