<prompt> Bhala ukuqhubeka kwalesi sigaba - Lapho kuqubuka isifo esikhulu  <response>: ngo-1854, uDkt. uJohn Snow waqoqa imininingwane ngamacala ngamanye, ikakhulukazi indawo yawo eSoho eLondon, esebenzisa izindlela ezintsha zokuhlaziywa kwendawo nokulandela umkhondo wokuthintana ukuze aphethe ngokuthi amanzi angcolisiwe yiwona ayeletha lesi sifo, futhi waphumelela ukuvala umthombo. Imephu eyayihambisana nombiko wakhe wango - 1855 yayibonisa izigameko ngazinye, zihlanganiswe endaweni ngayinye yendlu, zibonisa ngokucacile ukugxila ezungeze i - Broad Street Pump kanye nezikhala ezindaweni ezazineminye imithombo yamanzi. Ibalazwe manje selidunyiswa njengelishintshayo; nakuba indima yalo ekuphenyweni ngokwako nomphumela walo ekuxazululeni impikiswano ngesizathu salesi sifo kuvame ukucatshangelwa ngokweqile, lifanelwe ukuqashelwa ngokuqonda kukaSnow ukuthi ibalazwe laliyithuluzi elisebenza kahle kakhulu lokuxhumana namaphethini endawo yalesi sifo. 