M-bag surface mail travels the same way that regular surface mail does and is in the same class of service, so it is important to alert your customers that you are shipping this way so that they have realistic expectations.
M-bag air mail travels as first class mail. If you are using the M-bag air mail service be sure to tell the post office to put your package in the green air mail bag and to label/stamp it "air mail" generously. On more than one occasion, we have paid for air mail service, but because M-bags are always shipped in brown boxes, or boxes covered with brown paper, they are sometimes mistaken for surface mail.
There are two main disadvantages to M-bag service: it is not trackable, and it is not insurable by the post office. You can, however, purchase a "Certificate of Mailing" from the post office, which proves that you put the parcel in the mail, at a nominal cost. To insure M-bag parcels, use a blanket or one-time-only insurance policy from a carrier such as u-pic (www.u-pic.com) which covers all shipping nicely. If you are trying to send a package to a country that u-pic doesn't cover, you may wish to reconsider filling the order. They do not cover countries that have less than an 85% completion rate, or obvious global hot spots.
As soon as a parcel weighs over 4 lbs. we always consider sending it by M-bag. To compute the amount of postage for an M-bag parcel, do the following:
Go to www.usps.com
Select Calculate Postage
Select Calculate International Postage
Select Calculate Volume Discount Mail
Select International Volume Discount Mail
Select the country from the pull-down list (continue)
Select Economy M-bags (Books and Publisher's Periodicals) - do not select "Economy M-bags" as these non-book rates are higher, or Airmail M-bags if you are sending the books air mail (continue)
The Pieces field is a multiplier; if you are sending only one package in the bag, leave it at "1"
Type in the weight of the parcel to the nearest pound
Swann Maps & Atlases, Natural History & Color Plate Books December 9, 2025
Swann, Dec. 9: Lot 156: Cornelis de Jode, Americae pars Borealis, double-page engraved map of North America, Antwerp, 1593.
Swann, Dec. 9: Lot 206: John and Alexander Walker, Map of the United States, London and Liverpool, 1827.
Swann, Dec. 9: Lot 223: Abraham Ortelius, Typus Orbis Terrarum, hand-colored double-page engraved world map, Antwerp, 1575.
Swann Maps & Atlases, Natural History & Color Plate Books December 9, 2025
Swann, Dec. 9: Lot 233: Aaron Arrowsmith, Chart of the World, oversize engraved map on 8 sheets, London, 1790 (circa 1800).
Swann, Dec. 9: Lot 239: Fielding Lucas, A General Atlas, 81 engraved maps and diagrams, Baltimore, 1823.
Swann, Dec. 9: Lot 240: Anthony Finley, A New American Atlas, 15 maps engraved by james hamilton young on 14 double-page sheets, Philadelphia, 1826.
Swann Maps & Atlases, Natural History & Color Plate Books December 9, 2025
Swann, Dec. 9: Lot 263: John Bachmann, Panorama of the Seat of War, portfolio of 4 double-page chromolithographed panoramic maps, New York, 1861.
Swann, Dec. 9: Lot 265: Sebastian Münster, Cosmographei, Basel: Sebastian Henricpetri, 1558.
Swann, Dec. 9: Lot 271: Abraham Ortelius, Epitome Theatri Orteliani, Antwerp: Johann Baptist Vrients, 1601.
Swann Maps & Atlases, Natural History & Color Plate Books December 9, 2025
Swann, Dec. 9: Lot 283: Joris van Spilbergen, Speculum Orientalis Occidentalisque Indiae, Leiden: Nicolaus van Geelkercken for Jodocus Hondius, 1619.
Swann, Dec. 9: Lot 285: Levinus Hulsius, Achtzehender Theil der Newen Welt, 14 engraved folding maps, Frankfurt: Johann Frederick Weiss, 1623.
Swann, Dec. 9: Lot 341: John James Audubon, Carolina Parrot, Plate 26, London, 1827.
Sotheby’s Book Week December 9-17, 2025
Sotheby’s, Dec. 11: Darwin and Wallace. On the Tendency of Species to form Varieties..., [in:] Journal of the Proceedings of the Linnean Society, Vol. III, No. 9., 1858, Darwin announces the theory of natural selection. £100,000 to £150,000.
Sotheby’s, Dec. 11: J.K. Rowling. Harry Potter and the Philosopher's Stone, 1997, first edition, hardback issue, inscribed by the author pre-publication. £100,000 to £150,000.
Sotheby’s, Dec. 11: Wolfgang Amadeus Mozart. Autograph sketchleaf including a probable draft for the E flat Piano Quartet, K.493, 1786. £150,000 to £200,000.
Sotheby’s, Dec. 12: Hooke, Robert. Micrographia: or some Physiological Descriptions of Minute Bodies made by Magnifying Glasses. London: James Allestry for the Royal Society, 1667. $12,000 to $15,000.
Sotheby’s, Dec. 12: Chappuzeau, Samuel. The history of jewels, first edition in English. London: T.N. for Hobart Kemp, 1671. $12,000 to $18,000.
Sotheby’s, Dec. 12: Sowerby, James. Exotic Mineralogy, containing his most realistic mineral depictions, London: Benjamin Meredith, 1811, Arding and Merrett, 1817. $5,000 to $7,000.
![<b>Sotheby’s, Dec. 11:</b> Darwin and Wallace. On the Tendency of Species to form Varieties..., [in:] <i>Journal of the Proceedings of the Linnean Society,</i> Vol. III, No. 9., 1858, Darwin announces the theory of natural selection. £100,000 to £150,000.](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/00d5fd41-2542-4a80-b119-4886d4b9925f.png "<b>Sotheby’s, Dec. 11:</b> Darwin and Wallace. On the Tendency of Species to form Varieties..., [in:] <i>Journal of the Proceedings of the Linnean Society,</i> Vol. III, No. 9., 1858, Darwin announces the theory of natural selection. £100,000 to £150,000.")
