Patents. 433 
of commodities at home — for any thing hurtful to trade— -or gene® 
rally inconvenient. 
2dly. No patent is valid for any manufacture or invention in 
use at home before. 
Sdly. No manufacture or invention in use before, can be pro- 
hibited, or stopped on account of any patent granted for a new in- 
vention. 
4thly. The specification must be filed in chancery within the 
time prescribed. 
5thly. The specification must be full and precise ; sufficiently 
ample and intelligible in itself ; and must contain a plain descrip-' 
tion of every article, mode, process, and method, Necessary to 
enable an artist of reasonable skill in the subject matter, to suc- 
ceed in imitating the invention specified ; without further expla- 
nation, or the necessity of trying any preliminary experiment. Thi« 
complete disclosure, being the consideration for which the tempo- 
rary tTioncpoly is granted. Turnei'’s patent for making mineral 
yellow 5 was set aside for ambiguity. Sir Richard Arkwright’s 
patent for his cotton-spinning machine, was set aside (as I recol- 
lectj on account of his omitting to specify a weight and the place 
of it, necessary to make the machine go. A patent for elastic 
trusses was set aside, because the temper of the steel was im- 
proved by greasing it, which the patentee, who used tallow for the 
purpose, concealed. Any mode of misleading the public by am- 
biguity, concealment, or falsehood in the specification— by the in- 
troduction of unnecessary articles or processes, or the suppres- 
sion of such as are necessary, will be fatal to the patent right. 
The patentee must enable the public to use his invention upon as 
simple and easy terms as he uses it himself. 
6thly. The specification must pointedly describe the precise 
invention or improvement on which the patent is grounded ; so 
that the public may know specifically, what the artist claims as 
peculiar to himself : and in such manner, that any person contest- 
ing the patent, may be enabled to meet the precise claim of no- 
velty. It must not intermingle what was known before, with 
what is claimed as new, so as to render the latter ambiguous. 
The invention must be distinguished from what was previously 
known. 
7thly. If the patent be grounded on an addition to, or an im- 
provement of what was in use before, the patentee must confine 
his claim distinctly to the addition or improvement ; and not take 
©ut a patent including the inventions of others who have preceded 
