VESTA CROSSING, North Dakota — The county library has shortened its bookmobile route after returned books gained enough weight to lower the vehicle's rear suspension and exceed its recommended load. The books remain readable and show no increase in thickness, moisture or visible damage.
The Prairie County bookmobile serves nine towns and rural stops on a two-week circuit. Driver Noreen Bell first noticed the change Friday when three canvas return bags required two people to lift from a senior apartment lobby. The checkout list showed 41 ordinary books with a combined catalog weight of about 54 pounds.
On the library's freight scale, the bags weighed 173 pounds. Staff opened them and checked for stones, metal and water. A paperback gardening guide weighed 8 pounds 3 ounces, compared with 14 ounces for an identical copy. Its covers opened freely, and every page remained flexible.
The changes are uneven. Eleven books kept their recorded weights. A mystery borrowed but not opened, according to its patron, gained one ounce. A large-print poetry collection read each morning by Vesta Crossing resident Harlan Ose increased from 2 pounds to 37. Ose said he carried it to the return stop without difficulty and watched the bag settle sharply only after Bell accepted it.
Library workers have weighed 96 returns since Friday. Books read aloud or passed among family members tended to be heavier, but the pattern is not exact. A cookbook used for an entire church supper gained four ounces, while a short history consulted once for an obituary gained nearly 12 pounds. No patron has reported an injury.
The county removed four shelving carts and canceled two gravel-road stops Monday to keep the bookmobile within its axle rating. A smaller van delivered holds to those locations. Director Celia Marr said borrowers will not be charged for damage or asked to carry an unusually heavy item beyond a doorway; staff can arrange pickup with lifting equipment.
A mechanic found normal springs, shocks and tire pressure. At a certified truck scale, the emptied bookmobile matched its registered weight within 40 pounds. With the returned books shelved, it was 1,860 pounds heavier than the same inventory weights in the catalog, enough to change braking distance but not exceed the vehicle's legal limit.
Paper readily absorbs moisture, and bindings can conceal dense repairs, said book conservator Tal Orin, who examined six volumes. Moisture meters, infrared images and X-rays showed ordinary paper, glue and thread. Orin said the added mass did not pull at the bindings as expected; a 22-pound children's book could be held open by one corner without tearing.
Patrons have responded differently. Ose asked to renew the poetry book and accepted a library copy that still weighs 2 pounds. A farm family requested its returned picture atlas be kept at the branch because three children had traced every road in it during a storm. Marr said the library will preserve borrowers' privacy rather than publish titles beside measured weights.
Staff tested whether the change followed ownership by removing barcodes from two withdrawn books. Their weights remained stable. They then placed a heavy returned novel on the ground outside the vehicle; the scale still read 19 pounds. When its borrower touched the closed cover, she said it felt no heavier than before, although two employees could not lift it with one hand.
Before Tuesday's shortened route, children's librarian Mina Rell read a new board book aloud in the empty bookmobile as a control. It weighed 13 ounces before and after the reading. At the first stop, she read the same book to seven preschoolers and returned it to the scale. The dial rose slowly to 6 pounds while the children chose other books. It has remained there, and the narrow shelf beneath it now bows without touching either neighboring volume.