Inspection is one of the most important parts of an examination. The general appearance of the patient may be assessed: how does he move, does he appear ill, tired, does he look different from otherwise, what is the colour of his skin, and so on. The art of inspection was perfected at a time when no additional examination methods, such as our sophisticated laboratories and X-ray machines, were available. It may be performed with the unaided eye, or with the use of special instruments, for instance an endoscope. This telescope-like device enables axamination of the interior of body cavities and gives direct visual evidence of, for example, a tumour or ulcer. Inspection may simply consist of looking at something abnormal that the patient has noticed – for example, a skin rash or a lump. Part of the art of a skin specialist (dermatologist) lies in the ability to identify the plethora of rashes and other abnormalities by their appearance. Alternatively, inspection may form part of a general, preliminary examination, looking for outward signs of different disorders. For instance, many things can be discovered by examining the hands: paleness of the nail-beds and creases in the palms may indicate anaemia; tiny linear blood-spots beneath the nails may indicate a certain infection of the lining of a heart-valve; changes in the fingerends may accompany chronic chest disease; fine trembling of the fingers may indicate an overactive thyroid gland; certain kinds of very marked trembling indicate a disorder of the nervous system, and so on. Indeed, the list is almost endless, and is increasing. Inspection forms part of the examination of the various systems of the body. The chest may be scrutinized for abnormal heart beat that might indicate heart disease, and the abdomen inspected for swellings or distention, which may accompany bowel obstruction. For some parts of the body, inspection with special instruments is needed. For instance, an ENT (Ear, Nose and Throat) surgeon examines his patient with light from a head-lamp, or reflected from a head-mirror, thus illuminating the cavities of nose, mouth and throat and leaving his hands free to spread the nostrils or depress the tongue with other instruments. The ears are usually examined with an illuminated torchlike instrument, called an otoscope, containing a lens that magnifies the eardrum. An eye surgeon examines the patient with a lighted instrument termed an ophthalmoscope to inspect the retina; a special lamp, the slit-lamp, shows the cornea and eye-chambers with the aid of tangential light and magnification.