hand |
saw |
top 10 words in brain distribution (in article): body muscle form brain human bone tissue animal function allow |
top 10 words in brain distribution (in article): blade steel cut tool hand modern edge type material power |
top 10 words in brain distribution (not in article): cell wear horse type organism film structure image design woman |
top 10 words in brain distribution (not in article): iron head handle hair metal design nail size whip breast |
times more probable under hand 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under saw (words not in the model) | |
The hands'" (med. /lat.: manus, pl. manūs) are the two intricate, prehensile, multi-fingered body parts normally located at the end of each arm of a human or other primate. They are the chief organs for physically manipulating the environment, using anywhere from the roughest motor skills (wielding a club) to the finest (threading a needle), and since the fingertips contain some of the densest areas of nerve endings on the human body, they are also the richest source of tactile feedback so that sense of touch is intimately associated with human hands. Like other paired organs (eyes, ears, legs), each hand is dominantly controlled by the opposing brain hemisphere, and thus handedness, or preferred hand choice for single-handed activities such as writing with a pen, reflects a significant individual trait. What constitutes a hand? Many mammals and other animals have grasping appendages similar in form to a hand such as paws, claws, and talons, but these are not scientifically considered to be hands. The scientific use of the term "hand" to distinguish the terminations of the front paws from the hind ones is an example of anthropomorphism. The only true hands appear in the mammalian order of primates. Hands must also have opposable thumbs, as described later in the text. Humans have only two hands (except in cases of polymelia), which are attached to the arms. Apes and monkeys are sometimes described as having four hands, because the toes are long and the hallux is opposable and looks more like a thumb, thus enabling the feet to be used as hands. Also, some apes have toes that are longer than human fingers. Anatomy of the human hand. The human hand consists of a broad palm (metacarpus) with | A saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive. A saw may be worked by hand, or powered by steam, water, electric or other power. In a modern serrated saw, each tooth is bent to a precise angle called its "set". The set of the teeth is determined by the kind of cut the saw is intended to make. For example, a "rip saw" has a tooth set that is similar to the angle used on a chisel. The idea is to have the teeth rip or tear the material apart. Some teeth are usually splayed slightly to each side the blade, so that the cut width (kerf) is wider than the blade itself and the blade does not bind in the cut. The kerf of the blade is adjusted with a tool called a saw tooth setter. An abrasive saw uses an abrasive disc or band for cutting, rather than a serrated blade. According to Chinese tradition, the saw was invented by Lu Ban. In Greek mythology, Talos, the nephew of Daedalos, invented the saw. In fact, saws date back to prehistory, and likely evolved from Neolithic tools or bone tools. The early ancestors of man, in the Pleistocene era, likely first used a jaw bone of 5 bovid animals as a saw. Types of saw blades and the cuts they make. Blade teeth are of two general types: Tool steel or carbide. Carbide is harder and holds a sharp edge much longer. Materials used for saws. There are several materials used in saws, with each of its own specifications. |