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JOURNAL OP THE PLYMOUTH INSTITUTION. 
SUGGESTIONS ON THE POPULARIZING OF ART. 
BY MR. H. VIGURS HARRIS. 
(Read February 2nd, 1882.) 
SANITARY SCIENCE. 
SYLLABUS OF LECTURE BY MR. A. R. DEBNAM. 
(Read February 9th, 1882.) 
A brief history. The disposal of sewage. Construction of sewers. 
Local drainage schemes. Sewer gas, and the ventilation of sewers. 
The open gratings in our narrow thoroughfares. Ventilation of 
drains and soil pipes. The medical profession and sanitary work. 
House drains and their disconnection from sewers. 
IS INSANITY ON THE INCREASE? 
SYLLABUS OF LECTURE BY DR. ALDRIDGE. 
(Read February 16th, 1882.) 
Importance of the subject. Who are the insane 1 For the present 
purpose a division into two classes necessary : (a) The registered. 
(b) The unregistered. In estimating the numbers and relations 
of each class different methods needful. The statistical method 
applicable to class a. The numbers and relations of class b only 
to be estimated in a general way by a review of many circum- 
stances ; such as the following : influence of advanced civilization, 
and the rapid development and diffusion of education, upon the 
production of insanity; examination of general mortality statistics ; 
probable growth of other nervous diseases ; tendency of such 
diseases to act as producers of insanity in the individual and the 
race. Conclusion. 
