158 Intelligence and Miscellaneous Articles^ 



verts all vegetable fibre into gum, and when the action is continued 

 for a longer period, into sugar, I found that cotton was metamor- 

 phosed much more rapidly by the sulphuric acid than flax. It is 

 therefore by means of concentrated sulphuric acid that cotton may 

 be removed from linen when mixed with it ; and this object may be 

 obtained by the following process : — 



The sample to be examined must be freed as perfectly as possible 

 from all dressing by repeated washing with hot rain- or river-water, 

 boiling for some length of time, and subsequent rinsing in the same 

 water; and I may expressly observe, that its entire removal is 

 requisite for the experiment to succeed. When it has been well- 

 dried, the sample is dipped for about half its length into common 

 oil of vitriol, and kept there for about half a minute to two minutes, 

 according to the strength of the tissue. The immersed portion is 

 seen to become transparent. It is now placed in water, which dis- 

 solves out the gummy mass produced from the cotton ; this solution 

 may be expedited by a gentle rubbing with the fingers ; but since 

 it is not easy to remove the whole of the acid by repeated washing 

 in fresh water, it is advisable to immerse the sample for a few in- 

 stants in spirits of hartshorn (purified potash or soda have just the 

 same eifect), and then to wash it again with water. After it has 

 been freed from the greater portion of the moisture by gentle press- 

 ure between blotting-paper, it is dried. If it contained cotton, the 

 cotton threads are found to be wanting in that portion which had 

 been immersed in the acid; and by counting the threads of the two 

 portions of the sample, its quantity may be very readily estimated. 



If the sample has been allowed to remain too long in sulphuric 

 acid, the linen threads likewise become brittle, or even eaten away ; 

 if it were not left a sufficient time in it, only a portion of the cotton 

 threads have been removed ; to make this sample useful, it must be 

 washed, dried, and the immersion in the acid repeated. When the 

 tissue under examination consists of pure linen, the portion im- 

 mersed in the acid likewise becomes transparent, but more slowly 

 and in a uniform manner, whereas in the mixed textures the cotton 

 threads are already perfectly transparent, while the linen threads 

 still continue white and opake. The sulphuric acid acts upon the 

 flax threads of pure linen, and the sample is even somewhat trans- 

 parent after drying as far as the acid acted upon it, but all the 

 threads in the sample can be seen in their whole course. 



Cotton stuffs containing no linen dissolve quickly and entirely in 

 the acid; or if left but one instant in it, become so brittle and 

 gummy that no one will fail to recognise it as cotton when treated 

 in the above manner. — Liebig's Annalen, Feb. 1847. 



THE PLANET HEBE*. 



On July 1, M, Henke of Driessen in Prussia, discovered another 

 planet, which appears to belong to the singular group lying between 

 the orbits of Mars and Jupiter. It was first observed accurately at 



• Communicated by J. R. Hin(|, E8q.,F.R.A.S. 



