134 DENSITY OF S()LIJT[0NS— MORRISON. 



Prof. MacGregor * having sliowii that in the case ol:" a great 

 many salts, the curves exhibiting the rekition of the density of 

 (lihite solutions to their percentage composition, are practically 

 (to the fourth decimal place of the density when it is expressed 

 in grms. per cu. cm.), straight lines, I have thought it well to 

 determine to what degree of concentration the same is true for 

 solutions of this salt. I find that the first four of the above ob- 

 servations may, to the fourth place of decimals, be represented 

 by the formula — 



D^o = 0.99827 + 0.0104G p. 



where T)^ is the density of solutions at 20° C, and 2^ the percent- 

 age of anhydrous salt in solution, 0.99827 being the density of 

 water at 20° C. according to Volkmann.f The third column of the 

 above table gives the densities of the first five solutions calculated 

 by means of this formula, and the fourth column, the amounts by 

 which the calculated values exceed the observed values. It will 

 be seen that for solutions containing 2.6 or 2.7 per cent, of an- 

 hydrous salt, or less, the curve referred to is, to the fourth place 

 of decimals, a straight line. 



Nickel Sulphate. 



No observations of the density of very dilute solutions of 

 Nickel Sulphate having, so far as I know, been made hitherto, 

 I have made the few which were necessary to extend our know- 

 ledge of the density of solutions of this salt to extreme degrees 

 of dilution. The solutions were prepared and their composition 

 and density determined in the way described in my former 

 paper, referred to above. The results obtained are given in the 

 first two columns of the foUowincf table : — 



» Trans. Roy. Soc. Can., Vol. VH, (1889), Sec. iii, p. 23. 

 t Wied. Ann., Bd. XIV. (1881), p. 260. 



