A CLOCK LAMP. 



759 



The principle of the invention (fig. 886) consists in the animal utilizing 

 all the force resulting from his dead-weight. A small box contains the dog 

 very easily. In the illustration we see the dog at rest, and in that case he 

 maintains his centre of gravity and exercises no force upon the wheel. 

 But when the box is inclined, the mere weight of the animal is sufficient 

 merely to turn the wheel in the direction of the arrows. The dog, finding 

 himself sliding away, naturally endeavours to move forward, and the rotation 

 of the wheel is continued ; the best results are obtained when the body 

 is placed entirely upon the descending line, and this result is owing only to 

 the weight of the animal. 



There is a resting-place, just above and outside the " endless " way 

 traversed by the dog. A basin with water is also provided for the animal. 



M. Robert was let to this discovery in the following way : He em- 

 ploys a large number of sewing- 

 machine hands, and finding 

 that the working of the ma- 

 chines had an injurious effect 

 upon the health of the workers, 

 he determined to substitute, 

 in part, other labour for that 

 of female hands. He then 

 thought out his " quadrupedal 

 motors," which are worked by 

 intelligent dogs. There is very 

 little trouble or expense con- 

 nected with the working, so 

 a great saving is effected, as 

 the dogs cost little, and are 

 cheaply fed. The result is 

 that M. Robert has four heavy 

 machines occasionally at work, 

 which are kept in motion by 

 dogs at a very small expense. 



A CLOCK-LAMP. 



The illustration (fig. 887) Fig. 88 7 .-A ciock-iamp. 



represents an ingenious 



arrangement, which, by means of combustion of oil in a lamp, indicates the 

 hour of the night. The design explains itself. Two vertical tubes are 

 fixed above the reservoir of oil. The left tube contains oil, and is markes 

 with the hours ; the right tube burns the oil as a lamp. 



The apparatus is so constructed by the inventor, M. H. Behn, that a 

 certain quantity of oil is consumed exactly in one hour between two gradua- 



