34 2 Dr. Pearson on expectorated Matter. 
water, that is, between five and six per cent, of the expecto- 
rated matter. 
3. The impregnating substances have been shown to be 
Muriate of soda, varying commonly between one and a half 
to two and a half per 1 000 of the expectorated matter — Potash 
varying between one half and three fourths of a part per 1000 — 
Phosphate of lime about half a part of 1000 — Ammonia, united 
probably to the phosphoric acid ; Phosphate, perhaps of mag- 
nesia ; Carbonate of lime ; a Sulphate ; verifiable matter, or 
perhaps silica ; and oxide of Iron. But the whole of these last 
six substances scarcely amounting to one part in 1000 of the 
expectorated matter, it would be useless to estimate the pro- 
portion of each of them. It is very probable that the propor- 
tions and quantities of these ingredients, vary much more than 
now represented in different states of disease and health.* It 
is very probable also, that some of the ingredients may occa- 
sionally be absent, and others of a different kind be present, 
agreeably to the different states, on different occasions of the 
other secretions. 
4. It is manifest that the different states of consistence of 
expectorated matter, are owing to the proportion of albumi- 
nous or coagulable oxide, but I purposely avoid giving an 
account of the different conditions of health, on which the dif- 
ferences of consistence depend. 
5. The thicker the matter, the smaller I commonly found 
the quantity of saline impregnation. Hence, in sudden and 
copious secretions of the bronchial membrane, the matter is 
asserted to be salt, and to feel hot. In such instances, the 
proportion of coagulable matter was small, but that of the 
* In one case, the opaque expectorated matter in a pulmonary consumption having 
been exsiccated to brittleness, became almost liquid after a night’s exposure to the air. 
