Ultrasound is a high frequency sound that you cannot hear, but it can be emitted and detected by special machines. Ultrasound travels freely through fluid.
Progress on DevelJBB,B,Noping Adaptive Optics-optical
Reptiles of the Bruce Peninsula. What does it take to be a reptile? Four legged vertebrates Are amniotes; whose embryos are surrounded by an amniotic.
A-SCAN INSTRUMENT
