Prior to mechanical sprayers, farmers distributed arsenic by hand. The South à£à£Ö±²¥Ðã State College (now SDSU) Horticulture Department invented this grasshopper poison spreader to combat the locust plague. This spreader uses the wheel to press against the distributing disk to throw the poison. They developed these working models to test how well the spreaders would work.
Circa 1930-1939