i80 Patents. [Ch.X. Seclf. confined solely to the improvement; as the public have a right to purchase the improvement by itself, without being encum- bered with other things {a). Therefore where the inventioir was of a particular movement in a watch, and the patent was taken out for the whole watch, it was held void (6). A mere principle will not support a patent, because it is the first ground or rule for arts and sciences, or in other words^ the elements and rudiments of them. A patent must be for some new production from those elements which is vendible y for something of a corporeal and substantial nature, that can be made by man from matters subjected to his art and skill ; and not for the elements themselves (c). If, however, a new principle, or method of doing any thing ; or using old mate- rials ; be reduced into practice ; and be so far imbodied or connected with corporeal substances, as to be in a condition to act, and to produce a new result, the patent is sustain- able {d). There cannot be a patent for a mere philosophical principle, neither organized nor capable of being so ; but a patent for a machine improved by a philosophical principle,, though the machine existed before, is good. As laid down by C J. Eyre, in Boulton i Bull (e), " When the effect pro- duced is no substance or composition of things, the patent can only be for the mechanism, if new mechanism is used, or for the process, if it be a new method of operating, with or without old mechanism, by which the effect is produced. To illustrate thi-s, the effect produced by Mr. David Hartley's invention for securing buildings fi*om fire, is no substance or composition of things : it is a mere negative quality, the ab- sence of fire. This effect is produced, by a new method of disposing iron plates in buildings. In the nature of things the patent could not be for the effect produced, I think it could not be for the making the plates of iron, which, when disposed in a particular manner, produced the effect ; for those are things in common use. But the invention consisting in the , raethod of disposing those plates of iron, so as to produce their effect, and that effect being a useful and meritorious one. (a) Mr. Justice Buller in BouUon aud (c) 2 Hen. Bla. 463. 8 T.. R. 101. Watt V. Bull. 2 Hen. Bla. Rep. 463. 2 Barnew and Aid. 350. (i) Jessop's case, cited by Buller, J. (d) Ibid, in the same cause. (e) 2 Hen. Bla. 4j93. the