270 The Progress of Physical Discovery. [ 



chlorine, to which its properties are, indeed, in other respects, similar. 

 Several new vegetable substances were perceived about this time one 

 by Mr. Osborne of Dublin, in the saponarius officinalis ; and four by 

 Baup, viz. abietic acid in the resin of the pinus abies ; pinic acid from 

 the pinus maritima ; an extract from the Arbol a brea ; and elemine from 

 the Amyris elemifera. We should not omit also M. Bizio's discovery of 

 melaine in the ink of the cuttle fish ; a substance, black, light, without 

 taste or smell, heavier than water, and not affected by the air. 



Hansteen's experiments- on the intensity of magnetism in different parts 

 of the earth, are very numerous and interesting. His magnetic lines 

 determine the intensity for each given place ; the line J50" passing a 

 quarter of a degree south of Paris ; 775 " intersecting Amsterdam ; and 

 820" Edinburgh. The magnetic law varies gradually between the 

 equator and the pole, being at 45 as 1-2, and at 86 as 1"7 M. Sava- 

 rig's researches on electro magnetism are important, though it would be 

 impossible to give here any notion of their extent. But one of the most 

 striking facts ascertained this year, was, though simple, that of an Eng- 

 lish lady, Mrs. Sommerville, who effectually proved the magnetic powers 

 of the violet ray of light, by drawing the ray upon only one extremity of 

 the needle, the rest of it being concealed with a screen, when the extre- 

 mity submitted to the action of the ray constantly became a north pole, 

 and the other consequently a south one. The blue ray has a slight 

 power of producing this phenomenon, but the red and orange rays> 

 singularly enough, have none whatever. 



We cannot here forbear from noticing, though they are rather physio- 

 logical than physical, the very interesting investigations of Dr. Milne 

 Edwards, an English physician, residing at Paris, on the elementary 

 organization of living bodies. It appears from his " Recherches Mi- 

 croscopiques," published in this year, that the simple organic constituent 

 parts of plants and animals, (which, as far as they are capable of analysis 

 by us, are globules of the diameter of one eight- thousandth part of an 

 inch,) are capable when dissociated of independent life; that the death 

 of an organized complicated being does not destroy the capability of life 

 in its organic constituent parts, but that the decomposition of the entire 

 being gives life to these parts when separated. The constituent globules 

 can, it seems, only be deprived of life by being decomposed into their 

 ultimate chemical principles, viz. carbon, oxygen, hydrogen, and azote ; 

 for, so long as organization remains, there is a capacity for life. If any 

 thing was ever calculated to excite wonder and surprise, it is this dis- 

 covery. That our bones and muscles our fibres, hair, and nails and in 

 short, the solid matter of all animal and vegetable bodies contain the ele- 

 ments of life for myriads of individual beings ready to spring into action 

 at the dissolution of the greater fabric in which they are merged, is one 

 of the most remarkable truths that physiological science has yet brought 

 to light. Well may each of us now exclaim, in the words of the poet, 

 though in a more literal sense : 



Non omnis moriar ; multaque pars mei 

 Vitabit Libitinam ! 



The experiments of MM. De La Rive and Marcet, in 1827, upon the 

 specific heat of the gases, ascertained that under an equal pressure, 

 and with equal and constant volumes, all gases have the same spe- 

 cific heat; that all other circumstauces remaining the same, the 



