SOCIETY OK THE UNIVERSITY OF ABERDEEN'. 



121 



recting lenses was 548 or (58'5 per cent., after their adjustment 741 or 

 92'ti per cent. The difference between those is 193 eyes or 24'1 per- 

 cent, of the total number of eyes, so that nearly one fourth of the 

 eyes had normal vision only after an error of refraction had been 

 corrected. The number of eyes with vision below normal before any 

 error of refraction was corrected was 252 or 31-5 per cent., and of 

 those 252 eyes 193 or 70 per cent, of them obtained normal vision 

 after the proper correcting lenses had been adjusted. 



The number of eyes with vision less than ,,' ; ( y (which could not 

 read the type at 6 metres which an eye with normal vision could read 

 at 00 metres) was, before the correction of refractive errors, 43 or 

 5'37 per cent., after their correction 3 or '27 per cent. 



The following table shows the proportion of students with vision 

 normal in both eyes, normal in one eye only, or below normal in both 

 eyes : 



The above table shows that 3875 per cent, of the students had 

 vision below normal in one or both eyes without correction. It also 

 shows that 27 per cent, of the students with vision below normal in 

 one or both eyes without correction had vision improved to normal in 

 both eyes with correction ; 23 students or 5-75 per cent, had vision 

 improved to normal in one eye, the other eye having normal vision 

 before correcting lenses were tried, and 85 students or 21 '25 per cent, 

 had vision improved to normal in both eyes. Now, the number of 



students with vision below normal in both eyes without correction is 



16 



