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 j 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 Subsaiber. Januari/ 26. 1830. 



Cuvier's Zoology. — In the first volume of the Magazine of Natural His- 

 tory are some very useful articles, containing an epitome oiCuvier'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 subjudice. 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 bloody 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 y the association of ideas y imaginationy volition (what is meant 

 by volition?)y and reasoningy faculties. Tf the reader wUl give himself the 

 trouble to refer to what I have said, in my Lecture on the Mindy concerning 

 the term Facidtyy 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 smgular 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 scarce, comparatively speaking, deserves the name of goitre. 

 I have, after 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 in 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, 



