BAKER ON A NEW SCIENCE— THAT OF SANITATION. 77 



and observation, into a science; and its art, or tlie practical applica- 

 tion of its laws, has received the name of sanitation."* Herbert Spencer 

 has maintained that generally the arts have preceded the evolution of 

 the sciences upon which those arts were afterwards securely based. 

 Tills instance, mentioned by Dr. Smart, may, I think, be extended one 

 step further; because, as I shall endeavor to show, what he has called the 

 art of sanitation has now been developed "by study and observation, into 

 a science" — the Science of Sanitation. A science is knowledge which has 

 become accurate^ and systematically organized or arranged so as to 

 suppl}' general rules or laws. 



For the past twenty-five years a movement has been in progress in 

 Michigan which, during the past few years, has been crystallizing into 

 a Science of Sanitation. Sanitary arts have been practiced, and their 

 results have been observed and recorded, these records have gradually 

 become more accurate, they have been systematically arranged, so as 

 to evolve general statements or rules which year by year have been 

 found to be approximately uniform, until today it is possible by means 

 of this science to predict, with reasonable accuracy, what will be the 

 result of action or of non-action according to the arts of sanitation 

 which have been adopted in this State. When knowledge has been so 

 collected, recorded, and arranged, as to serve the purposes of prophecy, 

 it is worthy of being styled a science. Let me now introduce the evi- 

 dence that this has been done: 



Here are a number of diagrams, constructed accurately, representing, 

 according to fixed scales, the results of isolation and disinfection, and the 

 results of neglect of these two measures, in two diseases. A study of 

 these diagrams proves that, in two diseases (scarlet fever and diphtheria) 

 there occur about five times as many cases and deaths in those localities 

 where isolation and disinfection are not enforced as in those localities 

 in which these measures are enforced. The points to which I wish 

 here to ask attention are: (1) that — in a series of areas of about the 

 same extent, such as the townships, villages and small cities in Michi- 

 gan (the large cities being excluded), given the introduction of a case of 

 diphtheria or of scarlet fever, if nothing is done to restrict it the disease 

 tends to spread until, on the average, there have been about thirteen 

 cases, and two or three deaths. This is one general rule or statement 

 of fact. (2) Another general rule or statement of fact is that in a simi- 

 lar series of areas, given the introduction of a case of diphtheria or 

 scarlet fever, if isolation and disinfection are enforced not thirteen cases 

 and two or three deaths, but only about one-fifth of those numbers occur. 

 A compaiison of these two general facts, leads to a third general state- 

 ment, — that about four-fifths of the cases and deaths from scarlet fever 

 and diphtheria are prevented by isolation of first cases together with 

 such disinfection as has been practiced in Michigan under the direction 

 of the State Board of Health. 



*The Journal of the American Medical Association, Dec. 21, 1S95, p. 1070. 



