376 
COLLECTIONS AND RECOLLECTIONS. 
Hitherto we have observed, that this beautiful part of the flower is 
generally single, though in many cases formed of several portions. 
In some genera, however, it is double ; in Krameria, there are two 
nectaries, one above another; in Paullinia, there are also two, but 
differing from each other, one consisting of four petals inserted into 
the claws of the real petals, the other four glands at their basis, Clu- 
sia has tw r o sets of nectaries one within the other. 
In my next, I shall commence a description of the Linnean 
Classes and Orders, with a figure of each class. 
COLLECTIONS AND RECOLLECTIONS. 
ARTICLE XIV. 
On a New Method of Writing on Zinc, for Labelling 
Plants. —Mr. Henry Braconnot, the celebrated French Chemist of 
Nancy, to whom we are indebted for the curious transformation of 
rags and other similar vegetable substances into starch, gum, and 
sugar, by the agency of Oil of Vitriol, and whose name is well known 
in the chemical world for various researches connected with the 
analysis of vegetable substances, has given in the last number of the 
Annales de Chimie et de Physique, a preparation for writing on plates 
of zinc to label plants. The writer having a dislike to painting in 
oil, which is often inconvenient, and never endures a long time, re¬ 
solved to turn his attention to some other way which would prove 
both ready and durable. The system of writing on zinc with a black 
crayon, which was accidentally discovered by M. Symon an Ama¬ 
teur at Brussels, and noticed in the Revue horticole for October 1832 
and the Bon Jardinier for 1833, possessing many imperfections, Mr. 
Braconnot to try some experiments, being anxious to obtain a liquid, 
or a species of ink, which would be perfectly durable when exposed 
to the changeableness of the weather, and also one with which he 
could write with ease. This end, after several proofs, he is induced to 
believe he has in a great measure attained. If it answers he will 
have done both the botanists and amateurs a real service. The pre¬ 
paration is as follows:— 
Take Verdigres in powder one part, 
Salamoniac in powder one part. 
Lamp black (Mori de Fumea) half a part, 
Water ten parts; 
Mix these in a glass or pot mortar, at first only adding as much 
water as will mix it well, then add the remainder of the water, when 
placed in a vessel, let it be well shaked up from time to time and in a 
few days it will be ready for use. This is not only excellent for la¬ 
belling plants, but also for marking objects it is wished to preserve 
in low, wet, situations, and for marking key, becoming quickly dry 
and being very durable. 
T. HAKOCASTT.E, PRINTER, CHURCH-STREET, SHEFFIELD. 
