Place the face of the glass against the wall, in order to prevent dust from falling upon it. I have often dried the coating by holding or standing the glass adjacent to a stove. A steady heat is advisable, as it leaves the surface in a more perfect state, and free from any scum. After the coating is perfectly dry, it is ready for the preserving process. It should be warmed evenly, and when about milk warm, "Humphrey's Collodion Gilding" is poured on the image in precisely the same manner as the collodion. In a few seconds the coating sets, and after three-quarters of a minute, if it has not become dry, the blaze of a spirit lamp may be applied to the back and it will immediately become _perfectly transparent_, and nearly as hard as the glass itself: the effect is fully equal, if not superior, to that of chloride of gold in gilding the daguerreotype image. The surface becomes brilliant and permanent. The back of the glass can now be wiped and cleaned with paper or cloth, and gently warmed, and then with a common small brush one coat of black varnish can be applied. This brush should be drawn from side to side across the glass, and on the side opposite to that which has received the image. This is in order not to make streaks in the coating of varnish, but to have uniform lines across the entire length or breadth of the glass. If the varnish is of the proper consistency, it will flow into a smooth, even coating. After this first coating is dry, apply a second in the same manner, only in an opposite direction, so as to cross the lines of the first, uniting at right angles; when this last coating is very nearly dry, a piece of paper, glazed black on one side, and cut to the proper size, can be put next the varnish; it gives it a clean finish, at the same time that it aids towards a dense blackening. I sometimes apply the black varnish by flowing, in the same manner as in putting on the collodion. This picture is to be colored and put up in the same manner as the daguerreotype image, with a mat and glass. The last glass may be dispensed with by first using the collodion gilding, and then upon its surface apply the black varnish, as before. In this case the image is seen through the same glass it is on, and without being reversed: in this case the mat goes on the outside of the glass. When the image is seen through the glass upon which it is taken, it cannot be colored with very great success, as it cannot be seen through the reduced silver forming it. This forms a more or less opaque surface; but in point of economy the single glass is preferable. Yet I would not recommend such economy, for I consider that a good impression ought to be well put up, and the welfare of the art fully substantiates that consideration.