Page:Proceedings of the Royal Society of London Vol 69.djvu/369

Rh prosecrelin, which is present in relatively large amounts in the duodenal mucous membrane, gradually diminishing as we descend the intestine.

The prosecretin is apparently slightly soluble in 0'9 per cent. NaCl solution. It has no influence on the pancreatic secretion.

The secretin may also be split off from its precursor by boiling this with 0'9 per cent, saline.

The acid extract may be boiled, neutralised, and filtered without losing its activity. The active nitrate contains some primary albumoses, which may be precipitated by addition of large excess of alcohol and ether, and have no action on the pancreas. The alcoholic ethereal filtrate contains only a small amount of organic material, but on evapo- rating to dryness and taking up the residue with water, the solution obtained is as active as the original infusion.

These results indicate that secretin is probably a body of very definite composition, and of small molecular weight. Dr. Osborne is at present engaged in an investigation of its chemical characters and identity.

A chemical sympathy between different organs has often been assumed, as, e.g., between uterus and mammary glands, but we believe that this is the first case in which direct experimental proof has been afforded of such a relationship. It is probable, however, that this acid-duodenum-pancreas mechanism will prove to be but one of a whole class of similar mechanisms, the study of which should considerably increase our control of the various chemical function? of the body.

In the light of the results here noted, a revision of Pawlow's experi- .ments is necessary. In none of these latter was a possible expulsion of acid from stomach into duodenum excluded. We have so far failed to obtain a secretory effect on the pancreas by stimulation of the vagi, and are therefore rather sceptical of the alleged presence in these nerves of secretomotor fibres to the pancreas. We are continuing our experiments on this and kindred points.

A List of the Presents received was laid on the table, and thanks ordered for them.

The following Papers were read :

I. " The Chemical Origins of the Lines in Nova Persei." By Sir NORMAN LOCKYER, K.C.B., F.R.S.