574 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[January 14, 1871. 
was too much of this albuminous matter present, and 
that it remained and was inclined to do further work. 
One process which has been adopted to a considerable 
extent in the champagne districts, where that was sup¬ 
posed to occur, consisted in adding tannin, a substance 
which I have already spoken of, which carries down a 
good many albuminous bodies, forming a precipitate with 
them, and with these no doubt carries down the solids 
which may be in suspension. Then another process, 
which really bears a considerable resemblance to this one 
in principle, although not in form, is that of sulphuring, 
using sulphur in the casks, which, of course, you would 
understand at once, exerts an antiseptic action. It is, in 
fact, a process which consists in producing a material 
which is, in plain English, a poison to any germs which 
may happen to be present, whose action must consist, as 
far as it goes, in arresting the vitality,—in stopping any 
work which they were doing. M. Berthelot, who has 
made many accurate experiments regarding the compo¬ 
sition of wine and the changes which it undergoes, sub¬ 
jected some wine to the action of a known quantity of 
air, and by examining the wine afterwards he was led 
to the conclusion that air is an unmixed evil to wine 
when once it is fully made. There are certainly many 
general observations which everybody must have had 
occasion to make which agree with that. If wo open a 
bottle of wine and use half of it, especially if we leave a 
bottle of light wine open for some little time, everybody 
knows that it deteriorates in quality, and becomes flat, 
or even sour. In a great many cases, it is found that 
there is a development on the surface of the wine, and 
if you were to examine it carefully you would easily 
see, especially in light French or German wines, a 
pellicle—in fact, the vinegar cells; and their presence 
must have the effect of promoting the oxidation of the 
wine. M. Berthelot’s experiments confirm the general 
observation, which everybody makes more or less defi¬ 
nitely, that air is noxious to wine when present in any 
quantity. But M. Pasteur has arrived at precisely the 
opposite result. I do not mean to say that he says air 
cannot do harm, but that what is hurtful in air is the 
excess of it, or the too rapid rate of its action. He lays 
down the principle that every ripening of wine, or the 
process by which young and crude wine is changed into 
good old wine, consists in a process of slow oxidation; 
that is its very essence, and that without that, a crude 
young wine cannot be mellowed or transformed into a 
good old wine. The evidence which he gives for his 
conclusion is exceedingly simple, and I must say it 
appears to me exceedingly conclusive. He has, for the 
purpose of keeping wine with air, and for the purpose 
•of keeping it without air, resorted to appliances which 
.are far more effectual than those generally resorted to 
in common life. You may be aware that a cork, even 
what we should consider a good cork, does not com¬ 
pletely prevent the communication of external air with 
liquids in a bottle. I do not suppose many people can 
know how much air passes in and through a cork, 
but the quantity is very great. M. Pasteur sealed up 
some young green wine, by putting it into a glass 
vessel, and then he melted up the neck, so that he had 
no air present with it. He then kept it for a consider¬ 
able time, and he found that this wine, even after years’ 
keeping, was as green and as young as at first; that 
wine kept under conditions such as that air could have 
no access to it did not undergo, to any extent, the 
■change which was wanting, and that it did not im¬ 
prove by keeping. He then sealed up, in a similar 
vessel, some wine with air, and he subjected the wine, 
with a known quantity of air, to various influences 
which were calculated to accelerate the action of the air 
upon it, and amongst these I ought specially to mention 
that of light. He took some small vessels made of 
perfectly clear glass, and sealed up his wine, various 
qualities of it, in these little vessels with air, and then 
exposed them to the sunshine in the south of France. 
He found that the oxygen of the air was totally dis¬ 
solved, and that, when he examined the air, the oxygen 
had gone, but he found that his wine then did pass over 
rapidly into a state exceedingly like that into which it 
passes by the ordinary process of keeping in bottle. It 
lost its harshness, and became like old wine, which it 
resembled very greatly in its quality, and also in its com¬ 
position the older kind of wines. At the same time, he 
found that there was formed in such quality of wine a 
considerable amount of deposit, and his explanation of 
the way in which oxygen acts so as to improve the 
quality of the wine, is this, that it serves gradually to 
take away from the wine various substances which are 
present in it, and that the deposit is due to an oxidation 
of the colouring matters present, which have an unplea¬ 
sant, astringent, harsh taste, and it also consists in acting 
upon the alcohol of the wine and upon the various or¬ 
ganic liquids in it in a similar manner. This result is 
certainly one of very great importance; for if the process 
of improving wine requires the action of oxygen, and if, 
on the other hand, the action of oxygen may do much 
harm,—I mean if all the good has to come from the 
oxygen, and if all the worst evils come from oxygen,—and 
that really is the position in which the question stands 
upon our present evidence, it must be of the greatest im¬ 
portance to ascertain what are the conditions under 
which the beneficial action can be exercised, and what 
are those under which its detrimental influence occurs. 
In that respect, both of the observers I have mentioned, 
and others also, have established some remarkable facts, 
but in order to appreciate them duly, it will be neces¬ 
sary for you to know something of the general character 
of compounds to which I must now make allusion. When 
we were examining the process of oxidation, I spoke to 
you of alcohol as a substance eminently capable of under¬ 
going oxidation, and showed you how readily it could 
be burnt to a much smaller extent than that to which 
we are in the habit of burning it. I had to mention 
ordinary acetic acid as being a product of a shorter com¬ 
bustion. Here is a vinegar-plant which is oxidizing 
under alcohol, and there is an intermediate body which 
I have not yet spoken to you about specially. Here 
in this, I have some of it dissolved in alcohol. It is a 
substance which, in the strong state in which I have it 
here, has rather a sickly odour, and it was named by 
Liebig, to whom we owe some of the first and most 
accurate facts in relation to it, aldehyde, a name serving 
to recall one of the most important facts about it, viz. 
that it is alcohol from which hydrogen has been taken 
away. If you were to take away from alcohol some 
of its hydrogen, you would have aldehyde,—it is al¬ 
cohol minus one-third of hydrogen, and it is, there¬ 
fore, alcohol de-hydrogenized, and that is the origin of 
the term. When wines are undergoing very slow oxi¬ 
dation, it appears that aldehyde and other bodies analo¬ 
gous to it are formed. A great deal of evidence has 
been adduced of this, but I ought to mention that as 
yet one link in the chain of evidence is wanting, which 
chemists are always anxious to get in proof of their 
conclusions, that is, the substance itself, in a pure state, 
has not been obtained from wine. Still, the proof is so 
far conclusive that we are prepared to admit it pro¬ 
visionally'. One fact which I mentioned to y r ou just 
now is very remarkable, as part of the evidence, viz. 
that wines which are particularly good, either by r keep¬ 
ing or by r their own composition, combine with oxy'gen 
which is dissolved in them. Now, aldehy'de is particu¬ 
larly greedy of oxy'gen. If y'ou were to dissolve in 
the aldehy'de in this bottle some air, and if you were to 
try to get the air out of the alcohol again, you would 
find that y r ou could get the nitrogen of the air out 
again completely if y r ou went properly to work, but 
you could not get the oxy'gen out. The oxy'gen is laid 
hold of and digested so rapidly by the aldehy'de that it 
is no longer to be recovered, after even a very short in¬ 
terval of time. 
