ON CONCLUDING THE JOURNEY.
Complete your Collections.--When your journey draws near its close, resist restless feelings; make every effort before it is too late to supplement deficiencies in your various collections; take stock of what you have gathered together, and think how the things will serve in England to illustrate your journey or your book. Keep whatever is pretty in itself, or is illustrative of your every-day life, or that of the savages, in the way of arms, utensils, and dresses. Make careful drawings of your encampment, your retinue, and whatever else you may in indolence have omitted to sketch, that will possess an after-interest. Look over your vocabularies for the last time, and complete them as far as possible. Make presents of all your travelling gear and old guns to your native attendants, for they will be mere litter in England, costly to house and attractive to moth and rust; while in the country where you have been travelling, they are of acknowledged value, and would be additionally acceptable as keepsakes.
Memoranda, to arrange.--Paste all loose slips of MSS. into the pages of a blank book; and stitch your memoranda books where they are torn; give them to a bookbinder, at the first opportunity, to re-bind and page them, adding an abundance of blank leaves. Write an index to the whole of your MSS.; put plenty of cross-references, insert necessary explanations, and supplement imperfect descriptions, while your memory of the events remains fresh. It appears impossible to a traveller, at the close of his journey, to believe he will ever forget its events, however trivial; for after long brooding on few facts, they will seem to be fairly branded into his memory. But this is not the case; for the crowds of new impressions, during a few months or years of civilised life, will efface the sharpness of the old ones. I have conversed with men of low mental power, servants and others, the greater part of whose experiences in savagedom had passed out of their memories like the events of a dream.
Alphabetical Lists.--Every explorer has frequent occasion to draw up long catalogues in alphabetical order, whether of words for vocabularies, or of things that he has in store: now, there is a right and a wrong way of setting to work to make them. The wrong way is to divide the paper into equal parts, and to assign one of them to each letter in order. The right way is to divide the paper into parts of a size proportionate to the number of words in the English language which begin with each particular letter. In the first case the paper will be overcrowded in some parts and utterly blank in others, in the second it will be equally overspread with writing; and an ordinary-sized sheet of paper, if closely and clearly written, will be sufficient for the drawing up of a very extended catalogue. A convenient way of carrying out the principle I have indicated is to take an English dictionary, and after having divided the paper into as many equal parts as there are leaves in the dictionary, to adopt the first word of each leaf as headings to them. It may save trouble to my reader if I give a list of headings appropriate to a small catalogue. We will suppose the paper to be divided into fifty-two spaces--that is to say, into four columns and thirteen spaces in each column--then the headings of these spaces, in order, will be as follows:--
Verification of Instruments.--On arriving at the sea-level, make daily observations with your boiling-point thermometer, barometer, and aneroid, as they are all subject to changes in their index-errors. As soon as you have an opportunity, compare them with a standard barometer, compare also your ordinary thermometer and azimuth-compass with standard instruments, and finally, have them carefully re-verified at the Kew observatory on your return to England. A vast deal of labour has been wholly thrown away by travellers owing to their neglecting to ascertain the index-errors of these instruments at the close of their journey. A careful observer ought to have eliminated the effects of instrumental errors from his sextant observations; nevertheless it will be satisfactory to him, and it may clear up some apparent anomalies, to have his entire instrumental outfit re-verified at Kew.
Observations, to recalculate.--Send by post to England a complete copy (always preserve the originals) of all your astronomical observations, that they may be carefully recalculated before your return, otherwise a long period may elapse before the longitudes are finally settled, and your book may be delayed through the consequent impossibility of preparing a correct map. The Royal Geographical Society has frequently procured the re-calculation of observations made on important journeys, at the Royal Greenwich Observatory and elsewhere. I presume that a well-known traveller would never find a difficulty in obtaining the calculations he might desire, through the medium of that Society, if it was distinctly understood that they were to be made at his own cost.
Lithograph Maps.--It may add greatly to the interest which a traveller will take in drawing up a large and graphic route-map of his journey, if he knows the extreme ease and cheapness with which copies of such a map may be multiplied to any extent by a well-known process in lithography: for these being distributed among persons interested in the country where he has travelled, will prevent his painstaking from being lost to the world. Sketches and bird'[S-eye views may be multiplied in the same manner. The method to which I refer is the so-called Anastatic process; the materials can be obtained, with full instructions, at any lithographer's shop, and consist of autographic ink and paper. The paper has been prepared by being glazed over with a composition, and the ink is in appearance something like Indian ink, and used in much the same way. With an ordinary pen, with this ink, and upon this paper, the traveller draws his map; they are neither more nor less difficult to employ than common stationery, and he may avail himself of tracing-paper without danger. He has one single precaution to guard against, which is, not to touch the paper overmuch with his bare and, but to keep a bit of loose paper between it and the map as he draws. As soon as it is finished, the map is taken to a lithographer, who puts it face downwards on a stone, and passes it under his press, when every particle of ink leaves the surface of the paper and attaches itself to the surface of the stone, precisely as though it had originally been written there; the glaze on the paper, which prevents the ink from soaking into it, makes this transference more easy and complete. The stone can now be worked with, just as a stone that has been regularly lithographed in the usual manner; that is to say, printing ink may be rubbed over it and impressions may be taken off in any number. It will be observed that the writing on the paper is reversed upon the stone, and is re-reversed, or set right again, in the impressions that are taken from it. The lithographer's charges for furnishing autographic ink and paper, working the stone, striking off fifty copies of a folio size, and supplying the paper (common white paper) for the copies--in fact every expense included--need not exceed ten shillings, and may be much less. If before drawing his map the traveller were to go to some working lithographer and witness the process, and make two or three experiments in a small way, he would naturally succeed all the better. A map drawn on a large scale, though without any pretension to artistic skill, with abundance of profile views of prominent landmarks, and copious information upon the routes that were explored, written along their sides, would be of the utmost value to future travellers, and to geographers at home.