MECHANICAL PARADOXES. 



proximity to each other. These, acting in the 

 way described, can draw up oil to feed the 

 flame of a lamp. If a piece of cloth be arranged 

 as at K, one end dipping into water which nearly 

 fills a vessel, and the other end hanging down 

 outside, it can act as a siphon, the weight of 

 the liquid in the part outside favouring the 

 action much as it does in an ordinary siphon. 

 If a vase nearly full of water be arranged with 

 leaves or petals in the position shown at K, the 

 arrangement acts as a capillary siphon, and 

 speedily makes a considerable pool on the 

 mantelpiece or table. 



These are further cases of water running 

 uphill in defiance of the force of gravity. 



3. More Weight without more Material. 



The ordinary meaning of the word " weight " 

 is an earthward-tending force which can be 

 used as a measure of the quantity of material. 

 It depends upon the mutual attraction between 

 the material and the earth, and to make it an 

 exact measure of quantity careful observation 

 must be made of the latitude, the height, the 

 density of the fluid in which weighing takes 

 place, and so on. 



Another way of measuring quantity of 

 material is to note the energy with which it 

 strikes if stopped when moving. Here, again, 

 to be exact, we must observe the rate of motion, 



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