These microbes, most of which we can see, some of 

 which are still to be seen, have largely been enslaved by 

 means ,of the microscope. The sewage that fostered 

 their growth, and bred the seeds of typhoid and diptheria, 

 is used to grow our cabbages and lettuces on the sewage: 

 farm. The patch of land which yielded its increase in 

 hundreds, is watered with nitrifying bacteria, and there- 

 after yields its thousands. 



The Black Death that swept the land, and especially 

 London, in the middle ages, which altered the rates of 

 wages and the conditions of labour far more effectually 

 than any strike — that is stopped on the threshold. 



The Port Sanitary Authority and his ally, "the Micro- 

 scope," allow no case of plague to enter this country. 

 Smallpox, which used to ravage the country, by the simple 

 expedient of vaccination, is almost a forgotten fear. True, 

 its life history is not yet revealed by the micmscope,' 

 but by analogy we guess the story of its origin, and the 

 results of our treatment bear out the accuracy of our 

 surmise. Recent events have turned our thoughts to the 

 tropics, and there again the microscope has done a noble 

 work. India, Africa, America, even in their scorching 

 and pestilent ajeas, have been conquered by the 

 microscope. Ism;ilia, a few years ago one of the most 

 malarious districts on the earth's surface, is now a safe 

 and healthy spot. Sir Patrick Manson and Professor 

 Ross, of our tropical school of medicine, have used their 

 microscopes to some purpose. The malaria parasite has 

 been identified, and its life history made plain. Sir 

 Rubert Boyce, so recently an honoured citizen, has done 

 noble work in teaching us the source of yellow fever. 

 At the present time hopes are held of controlling the 

 sleeping sickness of Afjrica. All this research work would 

 have been impossible without the microscope. In Lftndon 

 Sir Almroth Wright has shown us how to identify a 

 special disease by its bacteria, how to prepare a vaccine 



