One Project Gutenberg book with many detailed survival-related tips in it (including a 18 page section on firemaking) is:
The Art of Travel
Shifts and Contrivances Available in Wild Countries
(5th edition, 1872)
Galton, Francis, Sir, 1822-1911
http://www.gutenberg.org/etext/14681You can download it in many formats, including MobiPocket (for a Kindle) or ePub (for a Sony Reader).
The 18 page firemaking section is pages 171-189: you can view it here:
http://www.google.com/books?id=73YBAAAAQAAJ&pg=PA277 There's an excellent section on signal mirrors (my specialty), both improvised ("makeshift") and purpose-built.
Alas, the two purpose-built devices (Galton's and Professor Miller's hand-heliostats) are no longer in manufacture.
The signal mirror section can be viewed at this link (with images)
http://www.google.com/books?id=73YBAAAAQAAJ&pg=PA277 )
and I've copied the text (only) here:
"Reflecting the Sun with a Mirror.--To attract the notice of a division of your party, five or even ten miles off, glitter a bit of looking-glass in the sun, throwing its flash towards where you expect them to be. It is quite astonishing at how great a distance the gleam of the glass will catch the sharp eyes of a bushman who has learnt to know what it is. It is now a common signal in the North American prairies. (Sullivan.) It should be recollected that a passing flash has far less briliancy than one that dwells for an appreciable time on the retina of the observer; therefore the signaller should do all he can to steady his aim. I find the steadiest way of holding the mirror is to rest the hand firmly against the forehead, and to keep the eyes continually fixed upon the same distant object. The glare of the sun that is reflected from each point of the surface of a mirror forms a cone of light whose vertical angle is constant, and equal to that subtended by the sun. Hence when a flash is sent to a distant place, the size of the mirror is of no appreciable importance in affecting the size of the area over which the flash is visible. That area is the section of the fasciculus of cones that proceed from each point of the mirror, which, in the case we have supposed, differs immaterially from the cone reflected from a single point. Hence, if a man watches the play of the flash from his mirror upon a very near object, it will appear to him of the shape and size of the mirror; but as he retreats from the object, the edges of the flash become rounded, and very soon the flash appears a perfect circle, of precisely the same apparent diameter as the disc of the sun: it will, in short, look just like a very faint sun. The signaller has to cause this disc of light to cover the person whose notice he wishes to attract. I will proceed to show how he can do so; but in the mean time it will be evident that a pretty careful aim is requisite, or he will fail in his object. The steadiness of his aim must be just twice as accurate, neither more nor less, as would suffice to point a rifle at the sun when it was sufficiently obscured by a cloud to bear being looked at: for the object of the aim is of the same apparent size, but a movement of a mirror causes the ray reflected from it to move through a double angle.
The power of these sun-signals is extraordinarily great. The result of several experiments that I made in England showed that the smallest mirror visible under atmospheric conditions such that the signaller's station was discernible, but dim, subtended an angle of only one-tenth of a second of a degree. It is very important that the mirror should be of truly plane and parallel glass, such as instrument-makers procure; the index glass of a full-sized sextant is very suitable for this purpose: there is a loss of power when there is any imperfection in the glass. A plane mirror only three inches across, reflects as much of the sun as a globe of 120 feet diameter; it looks like a dazzling star at ten miles' distance.
To direct the flash of the Mirror.--There are makeshift ways of directing the flash of the mirror; as, by observing its play on an object some paces off, nearly in line with the station it is wished to communicate with. In doing this, two cautions are requisite: first, the distance of the object must be so large compared to the diameter of the mirror that the play of the flash shall appear truly circular and exactly like a faint sun (see preceding paragraph): secondly, be careful to bring the eye to the very edge of the mirror; there should be as little "dispart" as possible, as artillerymen would say. Unless these cautions be attended to very strictly, the flash will never be seen at the distant station.
An object, in reality of a white colour but apparently dark, owing to its being shaded, shows the play of a mirror's flash better than any other. The play of a flash, sent through an open window, on the walls of a room, can be seen at upwards of 100 yards. It is a good object by which to adjust my hand heliostat, which I describe below. Two bits of paper and a couple of sticks, arranged as in the drawing, serve pretty well to direct a flash. Sight the distant object through the holes in the two bits of paper, A and B, at the ends of the horizontal stick; and when you are satisfied that the stick is properly adjusted and quite steady, take your mirror and throw the shadow of A upon B, and further endeavour to throw the white speck in the shadow of A, corresponding to its pin-hole in it, through the centre of the hole in B. Every now and then lay the mirror aside, and bend down to see that A B continues to be properly adjusted.
Hand Heliostat.--Some years ago, I took great pains to contrive a convenient pocket instrument, by which a traveller should be able to signal with the sun, and direct his flash with certainty, in whatever direction he desired. I did so in the belief that a signalling power of extraordinary intensity could thus be made use of; and, I am glad to say, I succeeded in my attempt. I at last obtained a pretty pocket instrument, the design of which I placed in the hands of Messrs. Troughton and Simms; and upon the earlier models of which I read a paper before the British Association in 1858. I called it a "hand heliostat." I always carry one when I travel, for it is a continual source of amusement. The instrument is shown in fig. 1 (p. 280), and its principle is illustrated by fig. 2. The scale is about 2/3.
E is the eye of the signaller; M the mirror; and L, S, fig. 2, a tube containing at one end, L, a lens, and at the other, S, a screen of white porcelain or unpolished ivory, placed at the exact solar focus of L: a shade, K, with two holes in it, is placed before L. Let R, r, be portions of a large pencil of parallel rays, proceeding from any one point on the sun's surface, and reflected from the mirror, as R' r' (fig. 2). R' impinges upon the lens, L, through one of the holes in K, and R' goes free toward some distant point, O. Those that impinge on the lens will be brought to a focus on S, where a bright speck of light might be seen. This speck radiates light in all direction; some of the rays, proceeding from it, impinge on the lens at the other hole in the shade K, as shown in fig. 2, and are reduced by its agency to parallelism with r' and R', that is, with the rays that originally left the mirror: consequently E, looking partly at the edge of the lens, and partly into space, sees a bright speck of light in the former, coincident with the point O in the latter.
What is true for one point in the sun's disc, is true for every point in it. Accordingly, the signaller sees an image of the sun, and not a mere speck of light, in the lens; and the part of the landscape which that image appears to overlay, is precisely that part of it over which the flash from his mirror extends; or, in other words, it is that from any point of which a distant spectator may see some part or other of the sun's disc reflected in the mirror. There is no difficulty in signalling when the sun is far behind the back, if the eye-tubes are made to pull out to a total length of five inches, otherwise the shadow of the head interferes. For want of space, the drawing represents the tubes as only partly drawn out. The instrument is perfectly easy to manage, and letters can be signalled by flashes. Its power is perfectly marvellous. On a day so hazy that colours on the largest scale--such as green fields and white houses--are barely distinguishable at seven miles' distance, a looking-glass no larger than the finger-nail transmits its signals clearly visible to the naked eye.
I have made a makeshift arrangement on the principle of my heliostat, using the object glass of an opera-glass for the lens, and an ordinary looking-glass: the great size and short focus of the object glass is a great convenience when using a mirror with a wide frame.
Professor W. H. Miller, the Foreign Secretary of the Royal Society, has since invented a yet more compact method of directing the flash, which he has described in the Proceedings of the Royal Society for 1865. It consists of a plate of silvered glass, one of whose rectangular corners is accurately ground and polished. On looking into the corner when the glass is properly held an image of the sun is seen, which overlays the actual flash. Beautifully simple as this instrument is, I do not like it so much as my own, for the very fact of its requiring no "setting" is its drawback. With mine, when the image of the sun is lost it is immediately found again by simply rotating the instrument on its axis; but with Professor Miller's the image must be felt for wholly anew."
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