The Wells Bequest by Polly Shulman (2013)

 

A very endearing young adult novel that follows the adventures of the pages who work at the New-York Circulating Library, a library that lends out magical items instead of books. We first met this library in the even-more-charming The Grimm Legacy. 

While researching robots, Leo discovers the New-York Circulating Library and the mysterious objects held within its walls.  Leo gets a job as a page at the library, mostly to be around the intriguing head page Jaya, but soon gets embroiled in time travel, death rays and other exciting developments.  Funny, adventurous and charming, and great fun for any fan of H.G. Wells. 

See also The Librarian's Note which explains how the librarian created call numbers for the mythical and magical objects in these two books.