EXHAUSTING SYRINGE. 



from the vessel K by this process. If we suppose the volume of the 

 cylinder through which the piston passes to be j^th, for example, 

 of the entire volume of the cylinder the tube and the connecting 

 pipe taken together, then it is clear, that on completing the first 

 downward stroke of the piston, ith of all the air included between 

 the piston and the surface of the vessel K will be expelled, and 

 r e Q ths will consequently remain. 



At every succeeding stroke, ^th of what remained after the 

 preceding stroke will be expelled, and in the same way T 9 5 ths 

 will remain. 



If we suppose the vessel R and the connecting tube to contain 

 ten million grains weight of air, the quantities expelled at each 

 successive stroke, the quantities remaining, and the total quan- 

 tities expelled from the commencement of the operation, will be 

 thus exhibited in the following table : 



Thus, in twelve strokes of the syringe, of the ten million of 

 grains of air originally included, something more than seven 

 million, or seven-tenths of the whole, have been withdrawn, and 

 something less than three-tenths remain. 



26. A rarefaction has been therefore produced in the pro- 

 portion of something more than three to ten. But it will be 

 apparent, that although by this process the rarefaction may be 



109 



