To excite this paper, dissolve thirty grains of nitrate of silver in one ounce of distilled water, and add a drachm and a half of glacial acetic acid; of this solution take one drachm, and one drachm of saturated solution of gallic acid[3], and add to it two ounces and a half of distilled water. The iodized surface of the paper may then be either floated on the surface of the aceto-nitrate of silver or exciting fluid, and afterwards a rod passed over, as was formerly done in the iodizing, or the aceto-nitrate may be applied evenly with a brush; but in either instance the surface should be immediately blotted off; and the same blotting-paper never used a second time for this, although it may be kept to develop on and for other purposes. It will be scarcely needful to observe that this process of exciting must be performed by the light of a candle or feeble yellow light, as must the subsequent development. The excited paper may be now placed for use between sheets of blotting-paper; it seems to act equally well either when damp or when kept for many hours, and I have found it good for more than a week. The time for exposure must entirely depend upon the degree of light. In two minutes and a half a good picture may be produced; but if left exposed for twenty minutes or more, little harm will arise; the paper does not solarize, but upon the degree of image visible upon the paper depends the means of developing. When long exposed, a saturated solution of gallic acid only applied to the exposed surfaces will be sufficient; but if there is little appearance of an image, then a free undiluted solution of aceto-nitrate may be used, in conjunction with the gallic acid, the former never being in proportion more than one-third. If that quantity is exceeded, either a brownish or an unpleasant reddish tint is often obtained. These negatives should be fixed by immersing them in a solution of hyposulphite of soda, which may be of the strength of one ounce of salt to eight ounces of water--the sufficiency of immersion being known by the disappearance of the yellow colour, and when they have been once immersed they may be taken to the daylight to ascertain this. The hyposulphite must now be perfectly removed by soaking in water, which may extend to several hours; but this may be always ascertained by the tongue, for, if tasteless, it has been accomplished. If it is deemed advisable--which I think is only required in very dark over-done pictures--to wax the negative, it is easily managed by holding a piece of white wax or candle in front of a clean iron rather hot, and passing it frequently over the surface. The superabundant wax being again removed by passing it between some clean pieces of blotting-paper. Although the minuter details can never be acquired by this mode which are obtained by the collodion process, it has the advantage of extreme simplicity, and by the operator providing himself with a bag or