From The Complete Works of Swami Vivekananda Volume 7- Chapter 4 – Notes Of Class Talks and Lectures
You preach to others to be men but cannot give them good food. I have been thinking over this problem for the last four years. I wish to make an experiment whether something of the nature of flattened rice can be made out of wheat. Then we can get a different food every day. About drinking water, I searched for a filter which would suit our country. I found one pan – like porcelain vessel through which water was made to pass, and all the bacilli remained in the porcelain pan. But gradually that filter would itself become the hotbed of all germs. This is the danger of all filters. After continued searching I found one method by which water was distilled and then oxygen was passed into it. After this the water became so pure that great improvement of health was sure to result from its use.