When the French set about creating a modern Vietnam, they decided to rebuild Hanoi using modern engineering skills. The city was famous for its drainage and sewer system. These sewers became the hiding and breeding points for rats. Because of these sewers they can travel from one part to another and entered well cared homes of French. Apart from education, deteriorating health and hygiene in the country also agitated Vietnamese and inspired the nationalist feelings among them. In 1903, the modern part of Hanoi was struck by bubonic plague Reasons for the plague are: (i) The French part of Hanoi was build beautifully with wide streets and a well-laid-out sewer system, while the 'native quarter' was not even provided with any necessary facilities. (ii) The waste and rubbish was drained straight out into the river so during the heavy rains or floods it would overflow into the streets. (iii) Thus, the sewers which were built to create a hygienic environment become the hiding and breeding point for rats and cause of the plague. As these sewers served as medium of transfer of rats into the city. (a) A 'Rat-Hunt' was started in 1902, to get rid of these rats. (b) The French hired Vietnamese workers for this work and paid them for each rat they caught. (c) Rats began to be caught in thousands but the money wasn't enough for the work Vietnamese doing. Those people who did the dirty work of entering sewers thought that if they came together, they could earn more money. (d) The bounty was paid when a tail was given as a proof that a rat had been killed. So, to earn more money the rat-catchers took to just clipping the tails and releasing the rats, so that the process could be repeated, over again. (e) Ultimately, the French were forced to stop the bounty programme. Besides this arrangement, the plague swept through the area.