134 ORGANISED FLUIDS. 



mucus and saliva which exist in the mouth at the time at 

 which the re-action of its secretions is tested, and which pro- 

 portion differs both at different times of the day, and in 

 different states of the system, and especially of the stomach. 

 The mucus of the mouth we know to exhibit in states of 

 health an acid re-action, \shile the saliva, on the contrary, 

 manifests an alkaline constitution ; the tendency of these 

 two fluids is therefore to produce a neutral secretion, and this 

 explanation will account for the opposite results which have 

 been obtained by different observers. The best time to as- 

 certain the chemical re-action of the buccal mucus is in the 

 morning when there is an accumulation of it on the tongue 

 and around the gums ; and the best method of determining the 

 acid or alkaline qualities of the saliva, is first to scrape the 

 tongue well, and as far as possible free the mouth of mucus, 

 and then proceed to test the saliva as it issues from the 

 orifices of its ducts. 



A highly acid condition of the mucus of the mouth is 

 assuredly productive of injurious effects upon the teeth. 

 Although this state of the buccal mucus cannot be regarded 

 as giving rise to the peculiar caries to which the teeth are so 

 remarkably liable ; nevertheless it cannot be doubted that it 

 predisposes the teeth to this affection, and that it hastens 

 greatly the progress of the decay when once this has com- 

 menced. To correct the condition of the stomach if it be 

 faulty, the internal administration of alkalies should be had 

 recourse to ; and to remedy the local acidity, tooth powders, 

 composed principally of some alkaline carbonate, should be 

 employed. 



The Vaginal Tricho-Monas. 



M. Donne has discovered in the vaginal mucus of women 

 labouring under discharges, either specific or otherwise, a 

 new species of human parasite belonging to the order of 

 Infusoria. This animalcule, owing to its resemblance to 

 the spherical mucous globules with which it is constantly 

 associated, is with difficulty discoverable by those who are 



