305 
produced by the slow action of the air, but they can only 
be looked upon as expressing the rate of one particular kind 
of change. The following table has been constructed from 
the whole of my observations, so as to give a good general . 
illustration of the subject. 
Column 1 shows the age of the wine in years and the date 
of the vintage. 
Column 2 gives the thickness of the diluted wine without 
sulphite, which produced the same intensity of absorp- 
tion as TOO inch of that to which the sulphite had been 
added. 
Column 3 shows the difference between the values in 
column 2, divided by the number of years between each two, 
so as to exhibit the amount of change for each year, after the 
wine had been kept for the various periods : — 
I. 
II. 
III. 
0 
(Made by myself ) . 
•22 
•2700 
H 
(1S66) 
■63 ’ 
•0700 
n 
(1865) 
•70 ' 
•0300 
(1864) 
•73 ' 
•0200 
44 
(1863) 
•75 
•0150 
54 
(1862) 
•764' 
•0150 
64 
(1861) 
•78 ' 
•0070 
94 
(1858) 
•80 ' 
•0030 
164 
(1851) 
•82 ’ 
•0020 
204 
(1847) 
•83 ’ 
•0008 
334 
(1834) 
•84 
•0007 
m 
(1820) 
•85 ’ 
Since the above table does not refer to wines of even years 
of age, I subjoin below another derived from it by laying 
down the results on paper as a curve, and interpolating by 
careful measurements : — 
