<prompt> Bhala okuqhubekayo kwalesi sigaba - Phakathi nobhadane lwango-1853-54, uFarr waqoqa ubufakazi obengeziwe bezibalo. Phakathi nesifundo esihlosiwe sokuqubuka kwekholera ngo-1854 eBroad Street  <response>: , udokotela uJohn Snow wasebenzisa idatha enikezwe i-GRO 