Academy of Science. 19 



and half a mile from the line of the Kansas Pacific Railway. They form a notable land- 

 mark to travelers. It in like manner forms the cap-rock of all the high hills of that 

 vicinity. It retains its thickness near Fort Wallace, bnt twenty-five miles south of Chalk 

 creek had decreased one-half, and the best agates were only in the cajjs of two inches. 

 The disintegration of the sand-rock would of itself give a poor soil. While this is its ■ 

 character in many places, in others we found a mixture of vegetation, which was fertile. 

 Springs and streams are not abundant, but where found (like others in sandstone regions), 

 the water is good ; and we will add, that in all our experience of eight summers' camping 

 in western Kansas, we have never met ivith a single "alkali" spring, or a single acre white ivith 

 alkali deposit. There are a few, and but a few, salt springs which may at some day be 

 made useful in furnishing settlers with salt. 



We have thus given a few notes of this important geological formation, showing how 

 little we yet know of our own territory. 



ON DETERMINING THE SOLUBILITIES OF METALLIC SALTS. 



BY PROFS. GEO. E. PATRICK * AND ALFRED B. AUBERT.f 



The determination of the solubility of a metallic salt in water or other solvent is appa- 

 rently a matter so simple and so easy of execution as to offer little difficulty to the chemist ; 

 and hence one would naturally expect that the results of different chemists, who have in- 

 vestigated the solubility of the same salt, would show the greatest concordance. But 

 notwithstanding this apparent simplicity, any one who has reviewed the subject must 

 admit that the results obtained by different workers in this field show a lamentable lack 

 of harmony. This lack of harmony must be due to the neglect of certain precautions 

 essential to accurate work, which precautions must relate to one or all of the following 

 points : 



I. Purity of material. 



II. Degree of saturation of the solvent at the temperatures at which the determinations 

 are made. 



III. Reliability of the process by which the amount of dissolved salt is estimated, and 

 accuracy in the execution of that process. 



Upon the first and third points the liability to error is comparatively slight, the exer- 

 cise of ordinary care only being necessary. But upon the second point there is the greatest 

 danger of error; for unless special precautions are taken, it is difficult to obtain a solution 

 at any given temperature, containing the normal amount of salt for that temperature, and 

 no more; for it is now quite well established that the ability to form super-saturated solutions, 

 so strikingly exhibited by sodic suli)hate, (Glauber's salt,) is likewise possessed in some 

 degree by all salts — by most, it is true, in so slight a degree as to be, under ordinary cir- 

 cumstances and for ordinary purposes, quite inappreciable, but in such a degree, however, 

 as to furnish ground for the belief that, unless cai-efully guarded against, it may, in the 

 determination of .solubilities, materially vitiate the results. Indeed, it seems probable 

 that to the phenomenon of super-saturation are due most of the discrepancies so appar- 

 ent between the diflTerent tables of solubilities. In support of this conclusion, we would 

 refer to the manner in which the determinations of solubilities have, as a rule, been 

 conducted. 



* Prop. Chemistry and Phvsics, Kansas University. fProf. Chemistry in Maine Agricultural College. 



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