The Accommodation of the Eye.

Waikato Times, Volume XXIV, Issue 1991, 11 April 1885, Page 2 (Supplement)

The Accommodation of the Eye.

According to physiological optics, the power of adjustment consists in the ciliary muscle and the crystalline len3e. Prof. Donders establised the fact that the human emmetropic eye is at its prime at the tenth year, attributing 14 dioptrics of additional accommodation at that period, and after that a gradual diminution, owing to the contraction of the ciliary muscle and the hardening of the crystalline lense, thereby losing its elasticity. It presents the question : Why is it that our eyes should begin to deteriorate so much earlier in life than the rest of our body, especially when we keep on developing up to middle age ? and whether or not at what time of life spectacles should be bad recourse to depends entirely upon the formation of the eye, and had better be determined by a competent oculist-optician. The ratio of deterioration reduces the amount of accommodation from 14 dioptrics at the age of 10 years, to 7 dioptrios at 30 years of age, and 1 dioptric at 55 yean.