SPECIFIC GRAVITY AND DISPLACEMENT OF SOME SALINE SOLUTIONS. 153 



Concentration 

 of the Solution 



in Ki-i'"- 



molecules per 



1000 Krams 



of Water. 



Results of Original Experiments. 



Results of Repeated Experiments. 



Difference 

 between ihe 



Mean Specific 

 Gravities in 



the two Series. 



Highest Value 

 ofSiiecific 

 Gravity. 



Lowest Value 

 of Specific 

 Gravity. 



Mean Specific 

 Gravity. 



Highest Value 

 of Specific 

 Gravity. 



Lowest Value 

 of S|iecific 

 Gravity. 



Mean Specific 

 Gravity. 



2/128 

 3/128 



7/128 



1-000662 

 1-001022 

 1002306 



1-000646 

 1-001000 

 1-002282 



1-000652 

 1001007 

 1-002294 



1-000672 

 1-001019 

 1-002309 



1-000647 

 1-000992 

 1-002292 



] -000655 

 1-001007 

 1-002298 



0000003 

 0-000000 

 0-000004 



Note. — The comparison of the figures given in the above table, where the greatest difference of the mean specific gravities 

 is 4 in the sixth decimal place, shows that the clianges in dis[ilacement of the solutions at tlipse concentrations are real, 

 and confirm the character of the changes in the values of dA and v, as shown in the table of original results. 



%, 7Q. The Arithmetic Series of Solutions having the Common Difference of 

 Concentration 1/64 gram-molecule. — Observations were made on the 5/64, 6/64, 7/64, 

 and 8/64 gram -molecule concentrations, as the 1/64, 2/64, 3/64, and 4/64 gram- 

 molecule concentrations were dealt with in the series having the common diiference 

 1/128 {vide supra). 



The solutions were prepared according to a scheme similar to the one described 

 in ^ 68. 



The following table gives all observed and derived data : — 



NaCl = 58-5. T=19-5°C. 



Weight of 

 '^- : Solution. 



Specific 

 Gravity. 



Displacement. 



Difference of 



Displace- 

 ments. 



Diflference of 

 Logarithms 

 of Displace- 

 ment. 



Mean Increment of 



Dis|ilaeenient per 



gram -molecule 



of Salt. 



Diiference of 

 Displacement 

 per gram- 

 molecule. 



m. 



1/64 

 2/64 

 3/64 

 4/64 



5/64 

 6/64 

 7/64 

 8/64 



W. 



1000-914 

 1001-828 

 1002-742 

 1003-656 

 1004-570 

 1005-484 

 1006-398 

 1007-312 



S. 



1000652 

 1-001295 

 1-001947 

 1-002636 

 1-003265 

 1-003920 

 1-004579 

 1-005166 



W/S = A. 



1000-262 

 1000-530 

 1000-793 

 1001-017 

 1001-301 

 1001-558 

 1001-811 

 1002-135 



dA. 



0-268 

 0-263 

 0-224 

 0-284 

 0-257 

 0-253 

 0-324 



d log A. 



-00011772 

 •00011303 

 -00009713 

 •00012295 

 -00011153 

 •00010962 

 •00014053 



V 



m' 

 16-768 

 16-960 

 16-917 

 16-272 

 16-653 

 16-619 

 16-558 

 17-080 



dA_ 

 dm' 



17-152 

 16-832 

 14^336 

 18^176 

 16^448 

 16^192 

 20-736 



§ 77. Displacement (A) and Difference of Displacement {d^). — Variations in the 

 values of dA. are obtained here as in the last series. 



The maximum value is 0-324 between m = 7l%^ and m = 8/64 gram-molecule 

 concentration, and the minimum is 0'224 between m = 3/64 and m = 4/64, comprising, 

 as it does, the interval represented in the former arithmetic series between m = 6/128 

 and m = 8/128, including the two low values of 0*110 and 0*114, 



There is a sudden rise to the high value 0*284 between m = 4/64 and m=5/64, 

 comparable with the change between m = 2/128 and m = 3/128 in the earlier arithmetic 

 series. 



TRANS. ROY. SOC. EDIN., VOL. XLIX., PART I. (NO. 1> 20 



