This is not a serious symptom when the acuteness of vision is not diminished; that is, if a person can read fine print with ease for a short time, even though the letters soon run together, the difficulty is probably a purely functional trouble which will be readily relieved by rest and tonic treatment. If there is blurred sight, with neither ability to read fine print nor to see small objects clearly even for a short time, the symptom is sufficiently serious to demand immedi ate attention from a good oculist. Blurred or weak sight can generally be relieved by the use of spectacles. In many cases the inability to use the eyes for any great length of time is due to some general disease, as nervous debility, dyspepsia, or cerebral congestion. These cases of course require improvement of the general health, or relief of the primary disorder.