6 



HARDWICKE'S SGIENC E-G OS SIP. 



grain solution is the one I now most frequently 

 use. 



In dye thus prepared, petals or leaves should 

 remain from two to twelve hours, being occasionally 

 examined, that they do not become too dark. When 

 taken out they should be washed for a few minutes 

 in the 95 per cent, alcohol, then be placed for about 

 four hours in absolute alcohol, then in oil of cloves 

 for one or two hours, preparatory to mounting in 

 gum dammar or Canada balsam. If not convenient 

 to work with this rapidity, the tissue may remain 

 in absolute alcohol for twenty-four, as in that time 

 but little colour will come out. In the cloves it 

 may remain still longer, as in it no colour is lost. 

 The absolute alcohol I use is manufactured by 

 Edward R. Squibb, of New York, U.S.A. A Ger- 

 man article I have tried bleaches out the dye, as if 

 it contained chlorine or some alkali. 



Aniline blue is the most beautiful and agreeable 

 colour to the eye that can be used. 



That which I have most used is a German blue 

 B.B., made at "The Berlin Aniline Manufactory," 

 Mannheim. It is granular in character, of a bright 

 golden-brown hue. 



Only two English brands have given me any 

 satisfaction ; the first is Nicholson's " Soluble Blue 

 Pure "—in appearance it is similar to the German, 

 only more golden in hue; the second is Nicholson's 

 " Soluble Blue, R.R." It is a cheaper article 

 than the former, and of a much darker shade. I 

 recommend it only when the former cannot be ob- 

 tained. 



"Nicholson's East Blue, B.B.B.," and an 

 "Opal Blue" manufactured by the same firm of 

 Brooke, Simpson, & Spiller, London, do not answer 

 at all, as they rapidly fade out on the dyed tissue 

 being placed in alcohol. 



In using other anilines the process is the same, 

 except as will be seen below. 



I have used, with partial and varying success, the 

 grey, violet, red, and green, about four grains to an 

 ounce of alcohol. The grey should have a few drops 

 ■of acetic acid added, and the green should be 

 brightened with picric acid. After removing the 

 stained material from the violet, red, and green, it 

 should be kept in alcohol and cloves for only a short 

 time, say half an hour each, as these colours rapidly 

 fade out. Besides the anilines, I have dyed with a 

 carmine solution made half as strong again as 

 Beale's, substituting water for the glycerine ; ako 

 a concent rated tincture of fresh berries of the 

 Phytolacca decandra. This tincture dyes very 

 rapidly, and not a trace of colour comes out when 

 the tissue is put in alcohol. It mixes w 7 ith the acid 

 aniline blue, forming purples. 



When dyes are acidulated, the alcohol used before 

 them should, also, be acidulated ; but when the 

 dyes are not, the alcohol should be pure. A well- 

 uhosen, and prepared leaf, mounted with the inferior 



side towards the cover-glass, on gradual focussing, 

 will show — 1st, hairs, if they are present, cells of the 

 inferior epidermis, and stomata; 2nd, cells of the 

 parenchyma and spiral vessels; 3rd, cells of superior 

 epidermis with a few stomata. 



Leaves should be small and young, not the 

 youngest. 



As much depends upon their selection. I will 

 mention a few that have given me the best results : 

 — Caculia urticulatu, Pteris -hastata, Hepatica 

 triloba, Oxalis stricta, or Oxalis lutea, Tropceolum 

 magus, Lonicera sempervirens, Tradescantia, Con- 

 volvulus, Adiantum; also the epidermis of the leaf 

 of Mesembryanthemitm crystallinum , and Dioncea 

 muscipula. 



It has long been known that alcohol and chlorine 

 will decolour vegetable tissue ; but the exact 

 method of decolouring, to prepare for dyeing, de- 

 scribed above, together with the dyeing, are original 

 researches. 



Baltimore, U.S.A., October, 1S74. 



[Dr. Beatty has kindly forwarded us specimens 

 of staining as above described, and we are able to 

 speak in the highest terms of their artistic beauty 

 and finish— Ed. S. £.] 



ALPINE BOTANIZING. 



THERE are few pursuits more calculated to 

 produce that very desirable state of things, 

 a mens sana in corpore sano, than botanizing in the 

 Alps or other mountain regions. Both mind and 

 body are fairly exercised, and not too much. It 

 is not a very :heavy mental strain to find out the 

 names of new plants, and the body need not go 

 through those wonderful gymnastics requisite 

 for the ascent of high peaks and glaciers and 

 which are not suited to all. The worst pedes- 

 trian can botanize in some verdant Alp, smooth as 

 a carpet, aud the most ^intrepid climber can find 

 vent for his energies in climbing the slippery moraine 

 or narrow ledges of the limestone rocks. Scenery 

 need not be neglected ; indeed, the eye, wearied by 

 continually gazing .at distinct objects, frequently 

 finds relief when the attention is, for a while, con- 

 centrated on some tiny floweret. The taste for 

 novelty, so strong in most of us, is gratified, as 

 species are far more numerous in the mountains than 

 jn the plains. Alpine plants beiug generally small 

 and compact, are dried with greater ease and make 

 better specimens for the herbarium than others. 



The best time, in ordinary seasons, for a month's 

 botanizing in the Alps, is from the middle of July 

 to the middle of August. More or less snow than 

 usual may make [this a fortnight earlier or later- 

 The Alpine pastures are, it is true, in their greatest 

 beauty early in June, but, although, at that time 

 i individuals are abundant, species are few, and the 



