Trials of Traction- Engines at Wolverhampton. 573 
■weight, 12 tons ; together, 38 tons ; steam, 120 lbs. When the 500 tcet mark was 
readied the wlicels were slippint^ badly, but were just driving; at 850 feet the 
slipjiing was excessive; the time occupied going between 600 and 800 feet was 
1 niiu. 28 sec. The steam had fallen from 120 lbs., at which it started, to 100 lbs. 
Alter the 1000 feet mark was jiassed the wheels slipped very much, but they 
drove, and at about 1350 feet, as the wheels got more polished, the engine was 
brought all but to a stand by the wheels slipping. At about 1400 feet there 
was great slipping. Coals and ashes were put under the wheels, and in that way 
the IGOO feet was reached. Here the progress was brought to an end, the wheels 
going I'ound with great violence. Here also was exhibited the disadvantage 
of the jack-in-the-box, for as soon as one wheel had turned a place for itself 
upon the road, so that it became more easy to drive than the other, the wheel 
which was less easy to drive stood absolutely still, and owing to the jack-in- 
the-box arrangement the whole energy of the engine was spent in " whizzing" 
round the wheel which was most easy to drive, for this a remedy was found in 
putting large stones under the easy-going wheel. We have already said that, 
in our opinion, the makers of locomotives for common roads should turn their 
attention to devising a ready means for putting the jack-in-the-box out of 
action ; nothing can be better than its jierformance under circumstances of an 
easy load and a fair road. Tlie power that it gives to turn, without disconnect- 
ing either driving-wheel, was well shown in the exhibition which took place at 
Stafford in the station-yard. It is true that the "Chenab" turned with great 
readiness, and in a very small circle ; but to enable it to do so, it was necessary to 
throw the driving-gear out of action with the wheel upon the inner side of the 
circle. The engines, however, that were fitted with the jack-in-the-box 
arrangement required no such care, and could be made without any alteration, 
•whatever to turn circles, first to the one hand and then to the other. To revert 
to the trial. At this point (the 1600 feet) the breaks were put on the waggons, 
the engine was uncoupled and sent ahead, and a chain put on to see if by these 
means the load could be started ; but it was without any effect, as the wheels 
fairly slipped round upon the I'oad at 1675 feet from the bottom. The Judges 
found that both wheels were slipping together very nicely, jaek-in-the-box not 
operating ; but this arose from a cold chisel having been put in between the 
teeth : the chisel, however, could not be kept in. After almost superhuman 
exertions on the part of Mr. Aveling and his assistants by feeding coals and 
stones under the wheels, and by the use of chains, the 1900 feet mark was 
reached in 29 min. 57 sec. from the time of starting at the foot of the hill. 
The weight upon the driving-wheels of this engine was SJ tons, the gross load 
38 tons, giving on an incline of 1 in 20, 1"9 ton as the resistance due to gravity ; 
and (adopting the same traction on a level, as before, namely, l-35th) 1"08 ton. 
would be the force required on a level, or together 2*98 tons, showing the 
adhesion of the wheel upon the road to be '35, as against the "^S of 
the indiarubber ; the insistnnt weight being unity in both cases. Although, 
the steepest gradient passed by this engine was 1 in IS, 1 in 20 has been 
taken, inasmuch as the passing over the 1 in 18 was really due to the use of 
stones and coals, and matters of that kind, and not to the fair adhesion of 
the wheels. 
By this time the " Sutherland " was fitted with its iron driving-wheels, which 
were 5 feet in diameter, 1 ft. 7-|in. wide on the faces, which were roimding, and 
were perfectly plain. The load drawn behind the " Sutherland" was 18 tons 
4 cwts. ; adding its own load, 10 tons, gave 28 tons 4 cwts. as the gross load. 
The steam at starting was at 140 lbs. To save time, the start was not made 
from the very bottom of the hill; but by the time the 500 feet mark was 
reached, the wheels began to slip; stones were introduced at 590 feet, as 
the wheels were slipping freely. From here iip to 1450 feet the travelling 
was good ; from 600 to 1300 feet was reached in 5 minutes and 5 seconds. 
