This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
Sago is an easily digestible form of starch derived from the pith found in the stem of different varieties of palm from Sumatra, Java, and Borneo. It is commonly sold in market in a granular form, and is known as "pearl sago." This is prepared by adding water to sago flour so as to form a paste which is run through sieves to granulate it. The spherical form of the granules is acquired by allowing them to fall into a shallow iron pan held over a fire. Sago is made with milk, cream, and eggs into nutritious puddings, and it may be used to thicken broths and soups of various kinds. It has an agreeable flavour, somewhat more delicate than tapioca, and is an invaluable adjunct to the invalid dietary.