88 C. E. Linebarger — Relations hetween the Surface 



liquids were quite insoluble in each other, by more than one 

 drop in a hundred. If, however, the liquids were somewhat 

 soluble in each other, quite variable results would be obtained 

 until the one liquid was saturated with the other. Thus water 

 in dropping up through nitrobenzene which was not changed 

 in three determinations gave for the first series : 1°, 136 drops 

 — 2°, 142 drops and 3°, 155 drops ; and for the second 1°, 

 133 drops— 2°, 146 drops and 3°, 161 drops. The first two 

 determinations agree fairly well ; they were made with water 

 dropping through dry nitrobenzene. But as the nitrobenzene 

 became more and more contaminated with water, the surface 

 tension of the liquids changed as shown above in the number 

 of drops. Three independent determinations of the number 

 of drops of water saturated with nitrobenzene up through 

 nitrobenzene saturated with water gave — 1°, 112 drops — 2°, 

 110 - 5 drops — 3°, 111 drops, — which are entirely concordant. 

 This slight solubility of liquids in one another complicates mat- 

 ters greatly, and renders stoichiometrical conclusions based upon 

 results obtained by measurements of superficial tensions of 

 liquids by the above method somewhat unreliable. Without 

 doubt, however, by a further study of these phenomena, we 

 shall learn how to make due allowance for such disturbing 

 influences. Of the liquids which I have examined, not one, 

 with the exception of nitrobenzene and bromoform, has given 

 any too variable results. 



The time of the growth of drops has a little influence upon 

 their size. For an elaborate investigation of the influence of 

 time upon drop-size I must refer to Guthrie's papers. In my 

 experiments, it was impossible to choose a certain fixed rate 

 at which all drops should form, since a large drop requires a 

 longer time for formation than a small one; hence I made 

 the drops form at such a rate as seemed necessary for the 

 attainment of the maximum size. 



In the case of liquids heavier than water, falling through 

 water, the orifice of the pipette was wetted by the water, and 

 hence the drops formed upon the inner circumference of the 

 orifice, which, however, in my instrument differed very slightly 

 from that of the outer. It was difficult to obtain concordant 

 results in this case, since the drops could not be prevented 

 from falling by " twos " and " threes." That is, a drop would 

 commence to form slowly, when, all of a sudden, it would 

 increase rapidly in size, fall off and be followed by another, 

 which would, however, take a longer time for formation. 

 There seems to be a sort of pull exercised by the first drop on 

 the second. Sometimes two drops would issue rapidly from 

 the orifice to be followed more slowly by a third. This, 

 rendering the rate of formation irregular, caused the results to 



