On auction there are four 18x24 cm and one 6½x8½ inches (whole-plate) wooden double dark slides There are two block form, two book form and one rolling form dark slides. There are also wooden reducing inserts: Two from 18x24 to 13x18 and 9x12 and two from 18x24 to 13x18. All the dark slides are light tight, maybe the block form types need care in extracting the draw-slide. Double dark slides were used with the early paper and dry processes and then for gelatine dry plates. There were three types of slide: Book Form - the slide opened like a book to load the plates Block Form - the plate slotted into the bottom of the slide where there was a removable panel, or clipped into the front of the slide when the draw-slide was removed. Metal or vulcanite draw-slides were normally fitted to this type of slide. Block-form slides were popular from the 1890s but date from much earlier. Rolling form - The slide rolls on the back in order to place the plates. Please see the photos provided. Package measures 39x29x14 cm and weighs 3,5 kg. Will be shipped in insured sturdy package by express courier.