"Tan Bark"

When one reads Henry French's book on Farm Drainage he mentions his "cellar drainage" was two rows of 2" clay tiles surrounded by "tan bark". What is this tan bark? Well in doing research on this subject I found that tan bark was probably the inner bark of the red oak tree. During the 1850's "tannin" was very desirable as it was used in leather tanning. I believe the tan bark was probably the bark that was left after the tannin was extracted.

At first I asked my self, "why would Henry French use tan bark around his cellar drains instead of river stone. Was it because of it being readily available? Easy to install? Well I must say that when doing research on iron bacteria and its affects on drainage systems, I came across two separate research studies, one in Scotland and the other in Florida. In each of these studies they found that the acid in conifer bark or in the case in Florida (oak bark) actually aided in controlling iron bacteria clogging drainage fields.

Could it be that in the 1850's Henry French knew that the tan bark would actually keep the cellar drains in his farm house in Concord, Massachusetts running freely.. (Note: I have been in this cellar of this house recently and did see that there was iron bacteria present.) Knowing what I do about Henry French and the Concord Farmers Group, I believe they did know. Some times when we want to learn something to help us with a problem, it is always a good idea to look at the things our ancestors did in the past and then ask why.