An ex-captain of the Salem militia is infuriated by the increase of crime on the streets â HIS streets! Although the Vigilante was fired for his violent and rash methods of war, he still has a strong sense of justice, or so he tells himself. As the death toll in the Town rises, his anger only grows as he finds the killer's identity obvious.
Dogs hear at a wider range of frequencies than humans.The low end of the range is similar: 67 Hz, but dogs hear noises up to 45 kHz, while humans only hear sounds up to about 23 kHz. This means that they could be hearing and responding to sounds that we can't hear at all.
The frequency of most dog whistles is within the range of 23 to 54 kHz, so they are above the range of human hearing, although some are adjustable down into the audible range. To human ears, a dog whistle makes only a quiet hissing sound. The advantage of the dog whistle is that it doesn't produce a loud irritating noise for humans that a normal whistle would produce, so it can be used to train or command animals without disturbing nearby people.