2009-01-222009-01-221903-08Indiana State Board of Health. Monthly Bulletin. 1903; 5(8) :90.0019-6754https://hdl.handle.net/1805/1763[Chalk dust remover]Fujitsu fi-4220c2, Adobe Photoshop CS3, 166 KBPage 90, center left approximately 2 1/2 X 1 1/4 in.Photograph in periodical.JPEGen-usAlthough these works may be freely accessible on the World Wide Web and may not include any statement about copyright, the U.S. Copyright Act nevertheless provides that such works are protected by copyright. Users must assume that works are protected by copyright until they learn otherwise.ErasersSimple MachinesSchool HygieneJones, J.A.(Plymouth)InventionsDustChalkIndianaInvention removing chalk dust from erasersstill image b&w photograph