674 



next folded up the specimen and placed it in other sheets of paper : 

 all the specimens T put up in the same manner. I then exposed them 

 to a gentle heat for thirty-six hours, and in that time I changed the 

 papers three times ; they were then taken out, and found to be quite 

 dry, with the colour of both leaves and flowers most beautifully pre- 

 served. Much might be said on the subject of drying botanical spe- 

 cimens, but structure is what I always wish to see preserved ; and as 

 for colour, I would say that white paper is decidedly the worst that 

 can be used, either for drying plants or keeping them in after they are 

 dried, owing to the extensive use of chlorine in the manufacture of it. 

 The enclosed specimen of Barbarea stricta was dried by artificial heat 

 in four minutes, and its colour, you will observe, is not in the least in- 

 jured. But as I am now taking up too much of your valuable space, 

 I will conclude by saying that Mr. Shepherd, of Mill House, near 

 Halifax, has a method of preserving plants, perhaps known only to 

 himself, which is decidedly the best I have ever seen, so far as colour 

 is concerned. The plan which he adopts is the fixing of their colours 

 by some chemical process, either before or during the progress of dry- 

 ing ; and I hope, before long, to prevail on him to give us the result 

 of his experiments on this subject. The following plants, dried by 

 Mr. Shepherd in the year 1838, are now enclosed ; they will serve to 

 show the merit of his plan in preserving the colours of plants : — ^Ana- 

 gallis arvensis, Epilobium angustifolium, Listera ovata. Orchis latifo- 

 lia, Sagittaria Sagittifolia and Myosotis sylvatica. — Samuel Gibson ; 

 Hehden Bridge, June 12, 1843. 



[Of Mr. Gibson's specimens, tliose dried quickly, by means of artificial heat, are 

 by far the most beautiful as regards colour and general appearance ; the foliage of the 

 Asperula No. 3 and of Barbarea stricta, has a perfectly natural hue, and their flowers 

 appear to be not at all injured for examination. The specimens which had been im- 

 mersed in hot water, have the least natural appearance of the whole number, and their 

 flowers seem lo be much injured. The specimens preserved by Mr. Shepherd, which 

 Mr. Gibson has had the kindness to forward, have the colours of their flowers most 

 beautifully preserved, but, with the exception of Sagittaria Sagittifolia, they do not 

 look quite natural. This may perhaps arise, in some measure, from their being gum- 

 med down to the papers on which they are placed, whereby the petals may have been 

 injured. The Sagittaria and Epilobium are decidedly the most beautiful of the whole, 

 and Orchis latifolia the least so, its flowers being apparently much injured. In a late 

 number of the ' Annals and Magazine of Natural History,' is an article on drying 

 plants by means of paper saturated with a solution of chloride of lime ; this being a 

 deliquescent salt, the moisture of the plants is said to combine with it, and while the 

 paper thus becomes wet, the plants themselves are dried in a short time. After all, 

 the only secrets in the art of preserving specimens of plants for the herbarium, are, to 

 use plenty of paper, and to dry the specimens as quickly as possible, either by means 

 of artificial heat or otherwise, with the aplication of only just so much pressure as will 



