2. The ashes are next examined for phosphate of lime. As wood, coal, and the other substances usually employed for heating purposes contain none or little of this salt, its detection in a notable quantity would lead to the inference that bones have been consumed. The ashes are allowed to digest for twenty-four hours with one-quarter of their weight of sulphuric acid. Water is next added to the pasty mixture, and the fluid filtered. If phosphate of lime be present, it is converted by this treatment into a soluble acid phosphate, which passes into the filtrate. Upon adding ammonia to the filtrate, a precipitate of neutral phosphate of lime is formed, neutral phosphate of ammonia remaining in solution. The fluid is again filtered, the filtrate acidulated with nitric acid, and then boiled with a solution of molybdate of ammonia likewise acidulated with nitric acid: in presence of a phosphate, a yellow precipitate, or at least a yellow coloration of the fluid, will be produced. It has been stated that the disengagement of sulphuretted hydrogen, upon treating the ashes with sulphuric acid, is an indication that the combustion of a human body has occurred; this reaction is, however, valueless, inasmuch as coal and certain vegetable ashes likewise evolve the gas when subjected to the same treatment. EXAMINATION OF WRITINGS. Contracts, checks, etc., are frequently altered with criminal intent, either by erasing the portion of the writing over the signature and substituting other matter, or by changing certain words, in order to modify the signification of a sentence. Writings are altered either by erasure or by washing. Erasure, although more easily executed, is seldom employed, as it renders the paper thin in places, and in this way leaves effects apparent even to the naked eye, and, although the original thickness can be restored by application of sandarac or alum, these substances possess properties differing from those exhibited by paper, and may, moreover, be completely removed, thus exposing the thinning of the paper. In case washing by means of chlorine has been resorted to, the sizing--which renders the paper non-bibulous, and which is only with difficulty replaced--may have been removed. Formerly paper was sized by immersion in a solution of gelatine; at present, however, a soap of resin, or wax, and alumina (a little starch being added) is more commonly used. In the latter case, the sizing is less easily removed by the action of water than when the gelatine preparation is employed; the detection of its attempted restoration is also a matter of less difficulty, as gelatine would be employed for this purpose, and this body possesses properties different from those exhibited by the substances normally contained in paper: iodine, for instance, which imparts a yellow color to gelatine, turns starch violet-blue. In order to detect the alteration of a writing, the following examinations are made: