At the beginning of the year 1906 I devised a new method of testing the functions of the digestive apparatus.1 It consists in giving the patient in a gelatinous capsule beads with various food substances attached and examining the feces with the stool sieve until all the beads are recovered. The latter are then inspected with regard to the presence or absence of the attached foods. Thus we see whether these have passed the digestive tract unaltered, or whether they have been digested.
TEST SUBSTANCES AND INDICATIONS.
Ordinarily, I give the following six test substances: 1, catgut; 2, fishbone; 3, meat; 4, potato; 5, mutton fat; 6, thymus gland. Physiologically, the two first substances (catgut and fishbone) are usually digested in the stomach and the remaining four (meat, potato, mutton fat, thymus) in the intestine.All the beads (or at least the greater part of them) usually appear in