Chloride of Aluminium and its Analysis. 24 1 



tusish, smooth, pistillate scale ovate, rather obtuse, a little smaller 

 than the fruit. 



Found by Dr. Riciiardson on the sea coast of Arctic America. 

 This is the species called by Dr. Richardson, C. filifolia of Nuttall ; 

 but this is a very different species except in size and leaves, and has 

 three or four staminate flowers at the base of the spikelet. 



Figures of the following species accompany this paper. 

 C. compacia, R. Br. Tab. U. fig. 63. 



— Carltonia, D. " " " 64. 



— Parryana, D. " " " 65. 



— arctica, D. " V. " 66. 



— aristata, R.Br. " '' " 67. 



— ursina, D. " " " 68. 



Art. VII. — Contributions to Chemical Science; by W. W. Math- 

 er, Instructor of Mineralogy and Geology and assistant Prof, of 

 Chemistry at the U. S. Military Academy, West Point. 



I. Chloride of Aluminium and its Analysis. 



A short notice was published in this Journal, Vol. xx, p. 408, of 

 some chloride of aluminium made by Wohler's process, in 1831, 

 and of some metallic aluminium, obtained by decomposing the chlo- 

 ride by means of potassium. The chloride of aluminium, was of a 

 sulphur yellow, crystallized, soft, volatile, slightly fuming in the air, 

 attracted moisture from the air and gradually deliquesced into a thick, 

 oily, lemon yellow liquid, of a greater density than water. The sol- 

 id chloride of aluminium, when put into water, emitted a sound Uke 

 that of a hot iron plunged in water, and dissolved completely, form- 

 ing a perfectly limpid and colorless solution. I find no account of 

 this chloride having been analyzed. Thomson in his Inorganic Chem- 

 istry calls it chloride of aluminium. 



In the reports of the British Association for the advancement of 

 science, page 492, the chloride of aluminium is said to be composed 

 of 2 al. + 3 cl., but without reference to any authority. 



Thomson and some others consider alumina as a protoxide of alu- 

 minium, and that the chloride derived from its decomposition would, 

 by the application of a general principle, be a proto-chloride. 



Probably Berzelius and Mitscherlich form their opinion of its be- 

 ■ ing a sesquichloride from an application of the same principle, the 



Vol. XXVII.— No.2. 31 



