ON THE CHEMICAL EFFECTS OF CHLORAL HYDRATE, ETC. 125 
Experiment 15.—Blood, with prussic acid added, and then 
oxalic acid, yielded red-coloured particles. 
Experiment 16.—Blood exposed to vapour of hydrate of 
chloral gave red particles as before; these lost their colour on 
addition of oxalic acid. 
Experiment 17.—Prussic acid and ammonia were mixed to- 
gether on a slide, and fresh blood added; red particles made 
their appearance; no starchy bodies; blood-corpuscles and 
plasma redder than usual. 
Experiment 18.—Blood, exposed to ammonia vapour, be¬ 
came slightly reddened; prussic acid added in fluid form; 
blood became decidedly redder; red particles and red plasma 
resulted. 
As far as these experiments had gone, I considered it rea¬ 
sonable to conclude that the decomposition of hydrate of 
chloral in the blood gave rise to the liberation of formyl, or 
else formate of ammonia. But what becomes of it? Is it 
likely to remain in a free and uncombined state? or rather 
does it not combine with that important element in the blood 
—iron, producing a formate of iron; or perhaps ammonio- 
formate of iron ? 
These decompositions in a highly complex material, as 
blood, are most difficult of explanation; and it is here I feel 
w r e must advance with caution. 
The next point to which I directed my attention was to 
ascertain the action of hydrate of chloral upon a salt of iron ; 
and the following experiments appear to me to support the 
view I have just expressed. 
Experiment. —Chloral dissolved in a little water with ammo¬ 
nia added, was followed by the decomposition of the former; 
a crystal of sulphate of iron was added, and the effect watched 
under the microscope; red-coloured particles and amorphous 
masses of different depths of tint, closely resembling those 
seen in the blood in the forementioned experiments, made 
their appearance. 
A solution of ammonio-citrate of iron also gives similar 
results, and somewhat similar also is the action of prussic acid 
and ammonia conjointly acting on a salt of iron. 
Again, being aware from experiments performed in times 
past, that the presence of iron in vegetable tissues was demon¬ 
strable by means of prussic acid and prussic salts, I pro¬ 
ceeded to make the following experiment, which, if it does not 
convince by its single testimony, yet is to my mind highly 
satisfactory; it is also one of the most remarkable of the kind 
which I can adduce, in relation to chemical action on vege- 
