+26.+ I intimated in the preceding paragraph that the candle went out in the receiver at the beginning of the distillation. The reason is to be found in the experiment which I have cited in § 13. In this case the acid of nitre, passing over in vapours, takes to itself the inflammable substance, whose presence is indicated by the black colour of the oil of vitriol; as soon as this has taken place it meets with the air, which again robs the now phlogisticated acid of its inflammable substance; by this means a part of the air contained in the receiver becomes lost, hence the fire introduced into it must go out (§ 15). +27.+ The acid of nitre can attract phlogiston in varying quantity, when it likewise receives other properties with each proportion. (_a._) When it becomes, as it were, saturated with it, a true fire arises, and it is then completely destroyed. (_b._) When the inflammable principle is present in smaller quantity, this acid is converted into a kind of air which will not unite either with the alkalies or with the absorbent earths, and with water only in very small quantity. When this acid of nitre, resembling air, meets with the air, the latter takes the inflammable substance from it again, it loses its elasticity (§ 13), the vapours acquire redness, and the air undergoes at the same time this no less remarkable than natural alteration, that it is not only diminished, but also becomes warm. (_c._) When the acid of nitre receives still somewhat less phlogiston, it is likewise converted into a kind of air, which, like the air, is also invisible, but unites with the alkalies and earths, and along with them can bring forth real intermediate salts. This phlogisticated acid is, however, so loosely united with these absorbing substances, that even the simple mixture with the vegetable acids can drive it out. It is present in this condition in nitre which has been made red hot, and also in _Nitrum Antimoniatum_. When this acid of nitre meets the air it also loses its elasticity and is converted into red vapours. When it is mixed in a certain quantity with water, this acquires a blue, green, or yellow colour. (_d._) When the pure acid of nitre receives but very little of the inflammable substance, the vapours only acquire a red colour, and are wanting in expansive power; it is, however, more volatile than the pure acid. This acid holds this small quantity of phlogiston so firmly that even the air, which so strongly attracts the inflammable substance, is not able to separate this from it. * * * * *