MISCELLANEOUS COMMUNICATIONS. 171 



which it imparts a deep red colour ; while potass dissolves it with a deep 

 brown colonr. It forms, with ammonia, a neutral soluble combination, and 

 another acid, insoluble or sparingly soluble, coloured red brown. The green 

 neutral combinations of the pure red colouring matter are changed in the 

 moist state, at the expense of the air, into this brown combination. The 

 precipitate of lead, however, constitutes an exception, since it is preserved 

 during washing and desiccation. 



Berzelius adds, that he has preserved for sixteen years, without change, 

 the green precipitate obtained from the fruits of the Mountain Ash (Sorbus 

 aucuparia), by the subacetate of lead, after having previously separated the 



malic acid by means of carbonate of lead Berzelius, Opere cicato. 



On the Red Colouring Matter of the Leaves in Autumn 



The foliage of certain leaves is observed in autumn to become led. All the 

 trees and shrubs on which Berzelius observed red leaves, bear also red 

 coloured fruits ; for instance, the Mountain Ash ( Sorbus aucupariaj, Cherry 

 ( Prunus ccmsns). Gooseberry ( Ribes groxsulmia), var. rubra, the Barberrv 

 (Bcrberis vulgaris j, and the like. The red colour contained in these leaves 

 is so near to the preceding that it may be pronounced identical. Berzelius, 

 nevertheless, examined only the red colour of the ioliage of the Cherry tree, 

 and especially the red Gooseberry, the leaves of the last of which often be- 

 come so red that they have completely the aspect of ripe fruits. Their 

 colouring matter was extracted by alcohol, which, after distillation, left a red 

 liquor, which was separated by filtering from a resin, and a fatty substance 

 precipitated. The filtered liquor was mixed with water, which was effected 

 without turbidity, and then with neutral acetate of lead, in which there was 

 formed a precipitate of a beautiful grass green, which, at the end of some 

 seconds, assumed a gray brown colour ; and acetate of lead was then added 

 until the precipitate no longer changed, and that last obtained preserved its 

 green colour. It was then separated by the filter, and what was left on the 

 latter is a combination of oxide of lead with the vegetable acids of the leaves, 

 and with a brownish colouring matter which is formed at the expense of the 

 air into red solutions, alcoholic and aqueous. The residual colouring mat- 

 ter was precipitated with a beautiful grass green colour by means of acetate 

 of lead, collected in a filter well washed, decomposed by sulphuretted hydro- 

 gen, and evaporated in vacw to dryness. The solution precipitated by ace- 

 tate of lead still furnished a small quantity of green yellow precipitate, when 

 free acetic acid had been there saturated by subacetate of lead. From this 

 precipitate was obtained a colouring matter entirely similar to the preceding. 

 This colouring matter, to which Berzelius gives the name of erythrophylle, 

 from t£vfyos, red, and <pv\*.ov, a leaf, were it only probably that of the fruits 

 while it is demonstrated to be so, is in aspect and chemical proportions simi- 

 lar to that of the Cherry and black Currant, and differs from them only 

 slightly in the shade of colour, which is a deeper red and inclines more to the 

 blood red, and in the property which it possess of forming green in yellow 

 combinations, while those of the colouring matter of the Cherry and Grape 

 are green or blue. The deposit formed by the evaporation of its solutions is 

 of a clearer brown red than that of the preceding, and gives with the bases 

 clearer brown red combinations, which do not so readily assume in the air B 

 dee]) shade, than i hat of the fruits. Bui whether these shades belong to the 

 deposit of the colouring matter in I he leaves, or are peculiar to the colour- 



