How did "Dadabhai Naoroji" discuss the concept of the "Poverty line" for the very first time in pre-independent India?

He used the menu for a prisoner and used appropriate prevailing prices for diet

In pre-independent India, Dadabhai Naoroji was the first to discuss the concept of a Poverty Line. He used the menu for a prisoner and used appropriate prevailing prices to arrive at what may be called the ‘Jail cost of living’. However, only adults stay in jail whereas, in an actual society, there are children too. He, therefore, appropriately adjusted this cost of living to arrive at the poverty line.