Mike

Metz was one of the depots for some of the Sapeur Battalions. (Alexandrie was another).

I did not see a 7th Bn. mentioned in many sources on google books, but I only have limited viewing for many of them.

In 1812, there were eight sapeur battalions which were reduced to five after losses in Russia.

The battalion was administrative and the individual companies of each battalion were the tactical units. These companies being assigned to Corps, etc. as needed without apparent regard to battalion organization.

Swords Around A Throne is probably the best place to start.

Swords Around A Throne. John R. Elting. Da Capo Press, 1997.

Preview only:

http://books.google.com/books?id=Xv5v4qDln_UC&pg=PA269&dq=

Good hunting.

Ron.