This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Vortex Ring Gun Chalk Test. en The image shows the flight of vortex ring laden with red chalk dust to enable visual inspection of the ability to transport and deposit particulate chemical agent onto target ft down range US Army Harry Diamond Laboratories George Kenneth Lucey Jr Toroidal vortices Lesslethal weapons Nonlethal and