THE PHYSICAL PROPERTIES OE METHYL- ALCOHOL. 



523 



temperature (corrected) ; h the level of the alcohol in the stem of the bottle ; 

 " Cap " the corresponding weight of alcohol in grammes ; St the weight of 1 c.c. 

 of alcohol of f, in grammes, reduced to the vacuum. In these reductions the 

 density of the air was assumed to be at the constant value of 1 *2 grammes per 

 litre, which is quite permissible in a case like the present : — 



Bottle No. I. 



Bottle No. II. 



t. 



h. 



Cap. 



4S f . 



h. 



Cap. 



4S«. 



0° 



4°-7 

 9°-7 

 14°-7 

 19°-7 

 29°-7 

 39°-7 

 49°-7 

 59°7 

 64°-7 



20-0 

 20-0 



7-0 

 19-9 

 20-0 

 20-0 

 20-0 

 20-0 

 20-0 



1-0 



16-3670 



16-2770 

 16-0955 

 160985 

 16-0088 

 15-8217 

 15-6305 

 15-4420 

 15-2380 

 150150 



0-810 24 

 0-805 69 

 0-801 20 

 0-796 66 

 0-792 09 

 0-782 64 

 0-772 93 

 0-763 41 

 0-753 12 

 0-748 25 



20-0 

 20-0 

 8-0 

 20-0 

 20-0 

 20-0 

 19-8 

 20-0 

 18-0 

 -2-5 



16-3845 

 16-2940 

 16-1155 

 16T195 

 16-0250 

 15-8370 

 15-6455 

 15-4580 

 15-2420 

 14-9910 



0-810 11 

 0-805 53 

 0-801 19 

 0-796 69 

 0-791 94 

 0-782 41 

 0-772 82 

 0-763 28 

 0-753 13 

 0-747 85 



The two bottles were immersed in the same bath. 



A preliminary survey of the results showed that, in accordance with 



AS 

 Mendelejeff's proposition, — — is very nearly constant, so that an equation 



S —S t = at+b? was sure to do sufficient justice to the observed relations. By 

 a proper combination of observations we arrived ultimately at the interpolation 



formula, 



S -S t = 90-53*+0-085057* 2 , 



which, as the following comparisons show, sums up the results satisfactorily : — 



t, 



0° 



4° 



9° 



14° 



19° 



29° 



39° 



49° 



59° 



64 



Specific Gravity at f = 4S«. 

 Calculated. Observed. 



•810 18 



•810 18 



•805 91 



•805 61 



•801 32 



•801 20 



•796 69 



•796 67 



•792 02 



•792 02 



•782 54 



•782 52 



•772 90 



•772 87 



•763 09 



•763 34 



•753 10 



•753 12 



748 05 



•748 05 



The alcohol used for these experiments had not been rendered air-free by 

 boiling, but we of course took good care, especially in the determinations at 

 higher temperatures, to make sure that there were no air-bells at the sides of 

 the bottle when the level in the stem was read off. To form an idea of the 



