What was the business opportunity presented to Damu Anna from Mumbai and why did it cause him turmoil?

As narrated in Chapter 25, a friend of Damu Anna's from Mumbai sent him a letter proposing a partnership in a cotton trading business. The friend assured him that it was a 'clean and safe' venture and projected a substantial net profit of two lakh rupees, which would be split evenly between them. The friend urged a quick reply, advising Damu Anna to be 'smart' and not let the opportunity pass, as he believed the price of cotton would rise instantly. This proposal caused Damu Anna's mind to be in a turmoil, likely due to the significant financial commitment and the need to make a swift decision on a speculative venture.