446 Retrospective Criticism. 
discovered them there? Who ever penetrated beyond 80°? In Vol. II. 
p- 473. is an extract from the Medico-Chirurgical Journal relating to the 
vulture and “ the toucan in India:” now, the toucan is not a native of 
India, and if the hornbill is meant, such, I can say from my own observa- 
tion, are not its usual habits; I scarcely ever saw it on the ground even, 
it keeping generally in close shady trees like the cuckoo. Such errors as 
I have noticed, tacitly sanctioned by being admitted without remark into 
your valuable magazine, can only serve to mislead or perplex your young 
zoological readers. — A Subscriber. January 26. 1830. : 
Cuvier’s Zoology. — In the first volume of the Magazine of Natural His- 
tory are some very useful articles, containing an epitome of Cuvier’s System 
of Zoology. There is, however, an observation (p.315.) which requires 
notice, as being calculated to mislead, namely, that which states that “ iron 
colours the blood.” It is true, soon after the discovery of oxygen, chemists and 
other philosophers stated that the cause of the red colour of the blood was 
a small portion of iron which is found in that vital fluid: but subsequent 
enquiries have not decided this to be the fact ; in truth, the cause of the red 
colour of the blood appears to be still sub judice. It will not be convenient 
to quote much from recent physiologists to show the truth of this pro- 
position ; but it may be necessary and useful to say, that Dr. Ure, under 
the article blood, in his Chemical Dictionary, observes : — “ No good explan- 
ation has yet been given of the change of colour which blood undergoes 
from exposure to oxygen and other gases ;” and Mr. Brande (Manual of 
Chemistry) says : —“ The iron appears to be regarded by Berzelius as con- 
tributing to the red colour of the blood ; a conclusion which my own expe- 
riments, detailed in the paper already quoted (Philosophical Transactions for 
1812), by no means warrant, and which is also at variance with the opinion 
of M. Vauquelin.”’ 
Another is the paragraph (p. 317.) calling, among other conditions of 
the mind, memory, the association of ideas, imagination, volition (what is meant 
by volition ?), and reasoning, FAcuLTIES. Jf the reader will give himself the 
trouble to refer to what I have said, in my Lecture on the Mind, concerning 
the term Faculty, he will soon see, it is presumed, the misapplication of 
the term Faculty to states and operations of the mind. I am yours, &c. 
— James Jennings. London, January 28. 1830. 
Goitre. (p. 191.) —In my Glance at the Beauties and Sublimities of Switzer- 
land (p. 161. to 165. inclusive), I have given an opinion on the cause of 
this singular enlargement of the thyroid gland, which I have investigated on 
the spot, in the valleys of Switzerland and Savoy. The conclusions which 
I have been led to form are the results of a careful revision of the facts 
collected, and I can hardly think that any other opinion can be formed. In 
this country it scaree, comparatively speaking, deserves the name of goitre. 
I have, aiter the descent of Mount Cenis towards Chambery, witnessed 
this glandular elongation so monstrous, that it required to be put up in a 
sack, and cast over the shoulders, not to impede their progress in walking. 
The hydriodate of potassa mixed up with lard, applied by friction externally 
as an unguent, has been found very successful in extirpating the goitre, 
even after it has attained a terrific size. I analysed almost all the fountains 
and springs in the canton of the Vallais, and found the water unusually 
pure i its chemical constituents, and free from extraneous matter mechani- 
cally suspended. A gentleman lately arrived from India has communicated 
some facts to me analogically confirmatory of my views on this curious 
and important subject. The water of the Hoogly branch of the Ganges ex- 
hibits a more reduced temperature, compared with that of the atmosphere, 
than is found in the Poonah branch of that river. In the former case, 
also, the ground is low, and presents a humid level, while in the latter it is 
mountainous, and swept by constant currents of air. In the Hoogly the 
Brahmins are accustomed to remain several hours during their ablutions, 
