An exception is a clause in a deed, by which the lessor excepts something out of that which he granted before by the deed. To make a valid exception, these things must concur:
1. The exception must be by apt words; as, saving and excepting, &c.
2. It must be of part of the thing previously described, and not of some other thing.
3. It must be part of the thing only, and not of all, the greater part, or the effect of the thing granted; an exception, therefore, in a lease, which extends to the whole thing demised, is void.
4. It must be of such thing as is severable from the demised premises, and hot of an inseparable incident.
5. It must be of a thing as he that accepts may have, and which properly belongs to him.
6. It must be of a particular thing out of a general, and not of a particular thing out of a particular thing.
7. It must be particularly described and set forth; a lease of a tract of land, except one acre, would be void, because that acre was not particularly described. ...