1. A METHOD OF TREATING ADHESIVE GUMS CONTAINING PRINCIPALLY MANNO-GALACTANS WHICH COMPRISES ADDING TO THE SUBSTANTIALLY DRY GUM PERACETIC ACID, HEATING THE MIXTURE SO OBTAINED TO A TEMPERATURE SUBSTANTIALLY ABOVE ROOMTEMPERATURE AND BELOW THE BOLIING POINT OF WATER, WHEREBY THE VISCOSITY OF SAID GUM IS REDUCED AND THE PRODUCT IS A SUBSTANTIALLY DRY MATERIAL, ADDING THERETO AN IN-TRALORGANIC NON-OXIDIZING, ALKALINE REACTING SALT FOR NEUTRAL IZING THE ACIDIITY OF SAID GUM, AND ADDING THERETO A SUBSTANCE TAKEN FROM THE CLASS CONSISTING OF GLYOXAL AND FORMALDEHYDE IN THE LIQUID STATE.