Page:Hardwicke's Science-Gossip - Volume 1.pdf/96

80 offer myself as a guide to give the benefit of my experience, and am induced to do this from having seen several papers on the mosses in various periodicals, evidently written by persons who had not studied what they wrote about; the advice given being rather calculated to mislead those who acted upon it. The first thing necessary (after making up the mind that, if anything is to be studied at all, it must be done in a proper, that is, in a scientific manner, and entails real work) is to provide a suitable text-book; and the only serviceable one in the English language on the British mosses is Wilson's "Bryologia Britannica." The next requirement is a microscope—we shall want two: a dissecting, and a good compounds microscope; likewise a pocket-magnifier; we shall also require a two-inch objective to the microscope. Without good magnifying power no real good can be accomplished. The following are also requisite: a gross of glass sides, 3 inches by 1; a gross of india-rubber rings, -inch diameter, outside measurement; an ounce of round, thin, glass covers, -inch diameter; some dead-black paper, and a steel punch, -inch diameter; a bottle of Canada balsam; a bottle of glycerine, to be mixed with equal parts of camphor-water; a bottle of asphalte; and a Shadbolt's turn-table, for making shallow cells; half-a-dozen glovers' triangular needles, for dissecting; a few camel-hair brushes; and a small vice, to fix on the table (this last makes a splendid section-machine, by placing the object between two pieces of cork, and with a sharp knife or razor, made flat on one side, taking a thin slice of the cork and object together); a few quires of blotting paper, and a memorandum-book, complete our requirements.

Before collecting, it will be advisable to get a general idea of the and  of the mosses; and this will be best accomplished by carefully studying the descriptions given by Wilson, at the same time constantly referring to his beautiful plates, until the family-likenesses are imprinted on our memory; and it is in addition a considerable help to enter into the memorandum-book all the most important parts of structure, and the principal distinguishing marks of the genera. We shall thus, from knowledge gradually and imperceptibly acquired, know when we get a Sphagnum, a Weissia, a Tortula, a Bryum, a Hypnum, &c.; and the genera more closely alike—as, Trichostomum and Tortula, Racomitrium and Grimmia, Dicranum and Campylopus—will also soon be easily distinguished.

Now for collecting; and all that is needful is a bag of good, strong material (such as lawyers use), a couple of newspapers torn into, say nine-inch squares, and a good, strong oyster-knife.

My advice is, eschew all tin vasculums. A moss having been found, take it carefully up (with the knife), wrap it in a piece of paper, and place it in the bag. The day's work finished, on arriving home we shall have clean, unbroken specimens, very different form the unsightly heap turned out from an ordinary vasculum. Having made out the names of several, we put the specimens into cold water, clean by means of a camel-hair brush, place on a white linen cloth, gently press them, and then lay on a sheet of blotting paper, with small slips bearing name, date, &c., cover with another sheet, and so on, put some large book on top to press—avoiding too great a weight; and when the specimens are dry, by means of gum fasten them on to the inside of the second leaf of a sheet of note-paper; write on outside of first sheet the family at top, the genus in the middle, and the species, habitat, &c., at the very bottom, commencing at extreme left hand. As, by the slightest pressure, mosses lose much of their character, it is requisite to have a quantity unpressed, but classified and arranged for reference. These specimens should be made up in paper bags formed of note-paper, thus—

Take half a sheet, turn up the lower edge to within half an inch of the top, fold the top over it, then turn the sides about half an inch over and inwards, open out the paper, and it will appear as represented in the above figure; cut away the dotted part, fold 1 on 2, then the sides 3 and 4 over that, and 5 over all. The bags thus formed will contain your unpressed specimens; write genus, species, habitat, &c., on the outside of No. 1, and arrange in cigar or other box.

We now come to the most fascinating part of our study, viz., the collection of microscopic dissections of leaves, capsules, peristomes, &c. These are invaluable even to the beginner. The first thing to be done is to take the -inch punch, and cut a number of circles of dead-black paper; gum these upon the centre of the 3-inches-by-1 slides; when dry, take