LABORATORIES AND PROBLEMS 



edge in many cases than he could obtain by actual visits 

 to the original institutions themselves. 



The same thing is true of various other features of the 

 subjects represented. Thus there is a very elaborate 

 model here exhibited of the famous Berlin system of 

 sewage-disposal. As is well known, the essential 

 features of this system consist of the drainage of 

 sewage into local reservoirs, from which it is forced by 

 pumps, natural drainage not sufficing, to distant fields, 

 where it is distributed through tile pipes laid in a net- 

 work about a yard beneath the surface of the soil. The 

 fields themselves, thus rendered fertile by the waste 

 products of the city, are cultivated, and yield a rich 

 harvest of vegetables and grains of every variety suit- 

 able to the climate. The visitor to this field sees only 

 rich farms and market-gardens under ordinary proc- 

 ess of cultivation. The system of pipes by which the 

 land is fertilized is as fully hidden from his view as are, 

 for example, the tributary sewage-pipes beneath the 

 city pavements. The average visitor to Berlin knows 

 nothing, of course, about one or the other, and goes 

 away, as he came, ignorant of the important fact that 

 Berlin has reached a better solution of the great sewage 

 problem than has been attained by any other large city. 

 Such, at least, is likely to be the case unless the sight-seer 

 chance to pay a visit to the Museum of Hygiene, in 

 which case a few minutes' inspection of the model there 

 will make the matter entirely clear to him. It is to 

 be regretted that the authorities of other large cities 

 do not make special visits to Berlin for this purpose; 

 though it should be added that some of them have 

 done so, and that the Berlin system of "canalization" 



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