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MR. RENNIE'S experiments ON THE FRICTION AND 



Remarks on Table X. 



The deductions to be made for the rigidity of the cord used in the foregoing experimente under 

 variable weights, as shown in the second and third columns, are nearly as the weights simply, and are 

 applicable to most of the cases in Table IX. 



Table XI. Experiments on the friction of Ice. 



A block of ice eighteen inches long and two inches thick, as free as possible 

 from air-bubbles, was accurately prepared so as to present a smooth, flat 

 surface, and was then fixed on the frame. A piece of the same block of ice, 

 but of smaller dimensions, was accurately prepared, and made to glide with 

 its flat surface over the bottom block, and a fine flexible silken cord attached 

 to it as in the former experiments. 



The weights in the first column indicate the insistent weights, and the weight 

 in the second column the moveable weights, llie experiments were made when 

 the temperature of the atmosphere was about 28 degrees of Fahr. 



REMARKS. — From the foregoing experiments it appears, that with ice on ice, friction diminishes 

 with an increase of weight, but does not seem to observe any regular law with regard to that increase. 



