THE INFLUENCE OF TOBACCO AND ALCOHOL ON VISION. 19 



average half an ounce daily. He related a case of a man who 

 smoked all day and when awake at night, and another of a cigarmaker 

 who smoked 40 cigars daily. Some persons were much more affected 

 by a small quantity of the "weed" than others; some consume 

 large quantities with apparent impunity. The local symptoms of 

 tobacco and alcohol poisoning are gradually increasing dimness of 

 sight affecting both eyes alike ; blindness for the lighter shades of 

 red and green ; the sight is better in the twilight ; nervousness ; 

 sleeplessness ; irregular appetite ; palpitation and pain over the 

 heart and loss of memory are the general symptoms. Most smokers 

 are alcohol users — but Dr. Ryerson related cases of total abstainers 

 who suffered from this malady, tobacco blindness. A majority of 

 cases are curable, but a certain proportion remain 2)ermanently blind. 



Mr. Macdougall asked whether Dr. Ryerson's statements 

 referred altogether to persons leading a sedentary life, or to 

 all classes. 



Dr. Ryerson. They referred to all classes. 



Mr. Macdougall said that he could smoke more when 

 engaged in active work. 



Mr. Elvins. Would alcohol alone produce those effects on 

 the vision ? 



Dr. Ryerson. It would not. 



Mr. Livingston. Would chewing alone produce them ? 



Dr. Ryerson. No. 



Mr. Williams called attention to the many cases of colour 

 blindness among railroad men arising from the use of tobacco, 

 so that a law had to be passed against it. 



The- President thought that a great deal of colour blindness 

 was not caused by the use of tobacco. More attention had 

 been recently paid to the subject, so that the cases were more 

 noticed. This accounted for the increase in the number of 

 cases. 



