1895.] 



Investigation of the Laws of Attrition. 



35 



Serpentine and Serpentine. 



"Weight per turn 

 per imit force. 

 Force. , A » 



42 47 33 



28 36 37 



28 33 37 



28 37 41 



28 35 36 



Mean = 0-000372. 



, r . „ . ,. , f First cylinder = 17*4. 



Mean circumference ot cylinders < _ J _. _ , h ., 



17 L Second cylinder = 17*3. 



Serpentine and Marble. 

 Force. Serpentine. Marble. 



28 285 142 



14 279 101 



14 242 137 



14 261 119 



14 273 135 



Serpentine = 0*000268. Marble - 0*00127. 



-, r . ■ £ p -i • -j [Serpentine = 17'2. 



Mean cirenmterence or cylinders { _ _ \ _ 



J I Marble = 150. 



Serpentine and Alabaster. 



Force. Serpentine. Alabaster. 

 28 53 210 



14 57 227 



14 71 200 



Serpentine == 0*000060. Alabaster = 0-00212. 



iine = 17*3. 

 Alabaster = 16*5. 



Mean circumference of cylinders I keipenti] 



I Alabaster 



Serpentine and Plaster of Paris. 



Plaster of 

 Force. of Paris. 



28 82 

 28 76 

 7 83 



Serpentine less tban errors of experiment. Plaster of Paris = 0*00803. 



Mean circumference of cylinders < ^f 1 P en ^ e 



3 I Plaster of Paris = 16*7. 



d 2 



