Help With These Revenues R229 With What Appears To Be Postal Precancels

Help with these revenues R229 with what appears to be postal precancels Lincoln Neb & Bay City Mich - does anybody know anything about them? Thanks

Yes, they are USPOD-applied precancels.

Like the temporary WWI 3c/2c letter and card rates of November 2, 1917-June 30, 1919, there was also a parcel tax in effect December 1, 1917-December 31, 1921, on domestic parcels rated at 25 cents or more, and required 1 cent tax per 25 cents (or fraction thereof) paid with revenue stamps. In other words, from Beecher & Wawrukiewicz' "U.S. Domestic Postal Rates," book:
0.01-0.24, no tax
0.25, 1 cent tax
0.26-0.50, 2 cents tax, etc

Add:
Here is an incredible example I owned briefly several years ago (although not using precancels), a piece of wrapper with 1.85 postage requiring 8 cents in revenue stamps. Sent from Hawaii Territory with two 75 cent parcel post stamps!


And a tag with 2.64 postage + 0.11 revenue:

Both precancels are listed in the PSS Classics 2A & 2B catalogs, Bay City 1.50, Lincoln 0.75

Although those are both very fine examples, because it was a parcel post tax and often used on wrappers, these types of tax usages are not all that common to find "on cover". Used singles are found fairly often, however. A shame the Hawaii piece does not still have both addresses, it would be a truly astounding item, and probably quite rare.

Thank you all for the help. Just did not remember seeing precancels on revenues. Now I know what they are, the reason for their use and value. Thanks again.