700 
T. W. TURNER. 
parent poorness of the vital fluid were looked upon as calling for 
the administration of iron. The intelligent employment of the 
metal advanced another step when it was discovered in the 
domain of physiology, that the activity of the blood, corpuscles 
as oxygen-carriers was dependent upon the presence of iron. It 
was found that the formation of new blood was also closely 
associated with the presence of tnis metal, so far at least as the 
abundance of red corpuscles was concerned, and that, what may 
be called the repair of the blood after severe haemorrhage, was 
greatly facilitated by supplying an abundance of iron. A sec¬ 
ondary question was naturally thus : In what form ought iron 
to be administered ? It forms two classes of salts, distinguished 
in earlier times as per- and proto-salts, and to-day by the adjec¬ 
tives ferric and ferrous. The various oxides, ferrous, ferric and 
ferrous-ferric played an important part, their activity being, of 
course, due to the solution of some proportion of the dose 
administered in the acid juices of the stomach. In later times 
various ferric and ferrous salts, oxides and hydrates, were used 
in medicine, as well as the metal itself in the finely-divided state 
known as reduced iron. There were, however, a number of dis¬ 
advantages associated with their prolonged administration, as 
was found to be the case in certain anmmic and chlorotic con¬ 
ditions. Among the soluble forms of iron the dialysed solution 
of the oxychloride was free from many unpleasant properties of 
most ferric preparations, but then its therapeutical activity was 
largely questioned by those who, regarding gastric absorption 
as partly dependent on a process of osmosis, asked how any 
liquid could be absorbed from which every constituent has been 
removed which was affected by the laws of osmosis. A more 
intimate study of the chemistry of the blood indicated that its 
contained iron was in the form of organic compounds of great 
complexity, and the idea suggested itself that it would be 
more rational to administer the remedy already in combination 
with some readily decomposable organic acidulous radical, than 
as an inorganic and very stable salts, which must be split up in 
the organism before the natural compound can be formed. As 
