_ On the Boiling-points of different Liquids. - $831 
The results obtained are, however, not unimportant, since the 
excessive values of 6 can easily be accounted for on the ground 
of eliptie polarization. 
If it be supposed, for example, that the difference of phase of 
the vertical and horizontal components is A, and that 6, is the 
change of direction when there is no elliptic polarization, an easy 
calculation gives 
tan 26, 
cos A? 
whence 6 must always be greater than 6,, their signs, however, 
being always the same. 
As experiment gave 6 positive, it confirms the result already 
obtained, that the vibration of polarized light is perpendicular to 
the plane of polarization. sid td. 
Copenhagen, June 28, 1860. 
tan 26= 
L. On certain Laws relating to the Botling-points of different 
Liquids at the ordinary Pressure of the Atmosphere. By 
Tuomas Tate, Hsq.* 3 
T is well known that the boiling-point of water is raised by. 
the addition of a soluble salt, or by the addition of a strong 
acid, and that this augmentation of the boiling-temperature de- 
pends upon the relative amount of salt or acid added, as the case 
may be; but, as far as I know, no general formule have hitherto 
been given to express the relation between the augmentation of 
boiling-temperature and the relative weight of the substance 
added to the water. 
Different weights of anhydrous salt being dissolved in 100 
parts of pure water, and the augmentation of boiling-temperature 
being observed, we obtain data for expressing the relation of the 
per-centage of the salt to the corresponding augmentation of 
the boiling-temperature of the solution. The salts which I have 
examined in this manner are as follows :—the chlorides of sodium, 
potassium, barium, calcium, and strontium ; the nitrates of soda, 
potassa, lime, and ammonia; and the carbonates of soda and 
potassa. I have found for all these salts, that the augmentation 
of boiling-temperature may be approximately expressed in a certain 
power of the per-centage of the salt dissolved: thus, if k be put for — 
the weight of dry salt in 100 parts of water, and T the corre- 
sponding temperature of ebullition above that of boiling water 
under the same atmospheric pressure, then 
Pht A sh: ai dliw (EX aoe ee 
* Communicated by the Author. 
