544 



NA TURE 



\_A71gust 12, 1880 



Their weight being considerable, the centre of gravity of 

 the combination is below the cork, and if the cork be 

 placed on the tip of the figure or on the lip of a wine- 

 bottle, it will stand there securely even while the bottle is I 



while the snipe's head nods at the various members of the 

 company in turn, and finally stops opposite one of them 

 (Fig- 4). 

 A pretty mechanical toy formerly sold in many shops, 

 but now rather rarely met with, is explained 

 , ; upon the principle laid down above. Two 

 ':'■■■• small wooden figures with large feet, and 

 holding a couple of poles palanquin-wise 

 Ijutween them, are set at the top of a flight 

 'if toy stairs. They descend performing 

 iimmersaults over one another. Fig. 5 shows 

 'mw the two figures are set at starting. The 

 _ (lies which they grasp are in reality glass 

 lubes plugged at the ends and containing a 

 mall quantity of mercury. The figures are 

 themselves made of very light wood, and 

 the cjuantity of mercury is adjusted to a 

 nicety, so that its position in the tubes 

 determines the position of the centre of 

 gravity of the combination. Fig. 6 shows 

 the position of the mercury in the end a of 

 the tube. At this stage of the movement 

 the figure marked R is still standing on the 

 topmost step. The other figure, S, is de- 

 scending, as shown by the arrow. The 

 position of the figure s, with the feet fore- 

 most, is determined by light silk threads 

 which connect the shoulders of r with those 

 of s, and in this position s has the advantage 

 in weight over the counterbalancing mer- 

 ' cury at a, hence S continues to descend 



until the tubes have passed the position in 

 emptied. I\I. Tissandier has revived another illustration which they are level. Once past this position the mercury 

 of the same principle which is capable of evoking roars ' rurs down from a to b and brings down s firmly on 

 of laughter at a dinner-table. If a dish of snipe has been , to his feet on the second step. At this juncture the 

 served up the head with its long beak may be fixed in a arrangement of the various parts will be that indicated 



•■rMm 



cork ; and then, two forks being thrust into the sides of 

 'he cork and a needle having been fixed into the lower 

 end of it, the cork can be balanced upon a coin laid on 

 the top of a wine-bottle, and can be spun slowly round 



in Fig. 7. The hands of S now become the pivot 

 about which the poles can turn and the mercury in b 

 is collected right in the bottom of the tube, where it 

 has the greatest leverage. The feet of R (which are 



