154 



MR. RENNIE'S EXPERIMENTS ON THE FRICTION AND 



Table V. 



Experiments on the Friction of two square inches surface of Wood at different 



angles of elevation. 



Weight on 

 surface. 



Moved at 

 degrees. 



Time in de- 

 scending 11 

 inches. 



Proportion. 



Weight on 

 surface. 



Moved at 

 degrees. 



Time in de- 

 scending 11 

 inches. 



Proportion. 



Red Teak on Red Teak. 



American live Oak on Red Teak. 



lbs. 

 10 

 20 

 28 

 56 



lbs. 

 10 

 20 

 28 

 56 



sec. 

 18 

 15 

 20 

 16 



7.116 

 7.348 

 7.861 

 8.144 



lbs. 

 10 



20 

 28 

 56 



00 

 00 

 30 

 45 



sec. 

 22 

 24 

 20 

 25 



6.314 

 7.116 

 6.691 

 7.348 



Black Beech on Black Beech. 



Norway Oak on Norway Oak. 



8 15 

 7 20 

 7 40 

 6 40 



sec. 

 20 

 17 

 19 

 21 



6.897 

 7.770 

 7.429 

 8.556 



lbs. 



10 



20 



28 

 56 



8 00 

 7 30 



7 00 

 6 20 



sec. 

 19 

 20 

 20 

 25 



7.116 

 7.596 

 8.144 

 9.010 



English Oak on English Oak. 



Elm on Elm. 



lbs. 

 10 

 20 

 28 

 56 



lbs. 

 10 



20 

 28 

 56 



lbs. 

 10 

 20 



9 30 

 8 30 

 7 40 

 7 30 



17 

 17 

 18 

 20 



5.976 

 6.691 

 7.429 

 7.596 



lbs. 

 10 

 20 

 28 

 56 



11 40 



10 30 



10 00 



9 30 



sec. 



19 

 18 

 19 

 19 



4.843 

 5.396 

 5.671 

 5.976 



Hornbeam on Hornbeam. 



Honduras Mahogany on Hornbeam. 



5.671 

 6.140 

 6.691 



6.897 



Yellow Deal on Yellow Deal. 



15 00 

 17 00 



sec. 



10 



9 



3.732 

 3.271 



Pine on Pine. 



sec. 

 14 

 11 



3.488 

 3.271 



lbs. 

 10 

 20 

 28 

 66 



12 00 

 12 30 

 11 45 

 11 20 



sec. 

 22 

 21 

 21 

 23 



4.705 

 4.511 

 4.808 

 4.990 



White Deal on White Deal. 



lbs. 

 10 

 20 



18 00 

 12 30 



10 

 11 



3.078 

 4.511 



