Report on the Trials of Iniplcmeyits at Bedford, 741 



obtained in all parts of the Delta in great abundance. In India, indigo-stalks, 

 and other indigenous vegetable substances, have been used in this way with 

 great success. Price 44.5?. 



5066. Clayton and ShuttJeworth, of Lincoln. — VariaUe Expansion Motion, 

 acted on hy the Governor, attached to al-horse-jwwer Portable Steam-engine. — 

 This is an adaptation of Meyer's valve motion, in which the variable cut-off is 

 .accomplished by altering the length of a cut-otf plate on the back of the 

 ordinary valve. The cut-off valve is moved by a second eccentric, and the 

 length of the valve is altered by moving two plates, of vv-hich it is composed, 

 by quick threaded right and left-handed screws cut on the valve of the spindle ; 

 this is capable of being turned by the rise and fall of the governor-balls, 

 through the agency of a toothed quadrant and pinion. The absolute sjwed of 

 the engine is determined by a circular weight keyed on the valve spindle, 

 which affects the rise of the governor, and can be slid along its lever for small 

 -adjustments, the larger changes being made by balls of different weights, 

 which can be readily applied (see Figs. 49 and 50, pp. 739 and 740). 



The spindle is not turned immediately Ijy the governor quadrant, but 

 through a slotted pair of discs, which permit the governor-balls to lift some 

 part of the distance without affecting the spindle. 



The engine runs very regularly with the steam-valve full open, and with loads 

 varying from nothing to the full power of the engine, or when lightly loaded 

 with steam full on, or only partially. 



5127. Bavey, Paxinan, and Co., of Colchester. — Patent Paxrnan Water-heater 

 No. 1. — This is an upright cyhnder placed at the side of a vertical-boiler- 

 engine. In tlie cylinder are placed eight hollow discs, having a circular hole in 

 the centre at top and bottom, 



and a central horizontal partition Fig. 51. — Messrs. Davey, Paxrnan, and 

 whicb does not quite extend to Co.'s Patent Faxman Water-heater 



the outer circumference of the _g_ JS^q^ \ ^q. 5127. 



•discs ; so that steam coming in 

 at the lower opening would re- 

 quire to pass along below the 

 partition and round its outer 

 circumference, and again over the 

 top of the partition, in order to 

 reach the upper opening. The 

 circular openings are closely con- 

 nected by india-rubber joints. It 

 will also be seen from the accom- 

 panying woodcut (Fig. 51), that 

 the discs are shallower at their 

 circumference than at their centre, 

 and that they do not extend quite 

 to the inner circumference of the 

 cylinder. Circular plates, d, are 

 fixed to the inner circumference 

 of the cylinder, and placed in 

 the interspaces formed by the 

 discs, leaving space to allow the water to [)ass downwards round the outer 

 surface of the discs. Thus it will be seen that the water enters at the top, 

 circulating downwards over the outside of the djscs, and passing out at G ; 

 while the steam enters at E, passing upwards through the discs, and out at h ; 

 there is therefore a complete circulation of both water and steam in opposite 

 directions, and thus a large and effective heating surface is obtained. 



VOL. X. — S. S. 



3 c 



