268 Dr. Meyer on the Gases of the Blood. 
supposition that in the latter case the alkaline bicarbonates are 
formed partly from the normal- and sesqui-carbonates, and partly 
also from the alkaline phosphates which are contained in the 
blood. That these latter salts play a part in the reaction is seen 
from the fact, that the 33-8 per-centage volumes of combined 
carbonic acid combine with only 33°8 volumes of additional gas, 
and leave 29-2 volumes unaccounted for. 
It appears from my experiments that little, if any, bicarbonates 
of the alkalies are present in the circulating blood ; as, in the 
first place, the quantity of carbonic acid which the blood gives 
up in the vacuum without addition of acid, agrees very closely 
with the amount which must be absorbed, in the strict sense of 
the word, at the temperature and under the pressure of carbonic 
acid contained in the air of the lungs; and secondly, that the 
blood when boiled, after the separation of this first portion of 
gas, does not give out any appreciable quantity of carbonic acid, 
whereas bicarbonate of soda very rapidly gives out half an equi- 
valent of carbonic acid, and continues to lose this gas, so that 
the solution gradually approaches the composition of the neutral 
salt. The absence of the bicarbonates in the blood is the more 
remarkable, as I have shown by absorptiometric experiments 
(Joc. cit.) that a dilute solution of normal carbonate of soda takes 
up from an atmosphere containing but little free carbonic acid, 
so much gas, besides that properly speaking absorbed, as is ne- 
cessary to form bicarbonate*. This phenomenon ceases when 
the amount of free carbonic acid in the gas diminishes to about 
1 per cent. 
From these experiments, however, it follows that if bicarbon- 
ates were once formed in the blood, they would not undergo any 
alteration in the atmosphere of the lungs. Hence it is evident 
that it is a mistake to imagine that these salts perform an essen- 
tial function in the phenomena of respiration. 
In opposition to the former views, my experiments show that 
the exchange of carbonic acid is, with a very great degree of pro- 
bability, to be regarded simply as a phenomenon of absorption ; 
whereas. in the case of the solution of oxygen, chemical forces 
also come into play. 
* J found in solutions free from air, which contained— 
zr Il. Ill. 
1:041 0°998 0-998 vols. CO? at 0° and 0™°76 in the 
at 23°6C k=1:087 0957 0981 ,, ,,  formof NaQCO®. 
a—O:S8185 08305 (0850 se pen 0 ass 
The numbers in column III. are calculated from experiments made with 
a mixture of carbonic acid and hydrogen. 
Bunsen found at 22°-4 C. «=0°864. Hence it is seen that the presence 
of a small quantity of a salt in solution does not materially alter the coeffi- 
cient of absorption. 
