and Observations on the component Parts of Membrane. 34,1 



quantity of carbonate of lime ; so that the result of this experi- 

 ment did not differ from that of the former. 



From the preceding experiments it appears, that the Gorgonia 

 nobilis or red coral, consists of two parts ; one of which is the 

 stem, formed of a gelatinous substance, hardened by carbonate of 

 lime, and coloured by some unknown modification of animal 

 matter ; the other is a membranaceous tube, which, like a 

 cuticle or cortex, coats the stem abovementioned, and (when 

 deprived of its hardening substance) possesses all the characters 

 of membrane. But, although carbonate of lime could only be 

 discovered, when this Gorgonia was simply immersed in acids, yet 

 it has been proved by these experiments, that a small portion of 

 phosphate of lime is also present, but so enveloped by the mem- 

 branaceous and gelatinous parts, as not to be dissolved by the 

 acid menstrua, till these substances have been decomposed by 

 fire. 



This is not an unusual circumstance, when a very small por- 

 tion of a substance is enveloped by large quantities of other 

 matter; for, Berg man n, in his supplement to Scheele's Essay 

 on the Calculus Vesica, observes, that the presence of calcareous 

 earth in certain calculi, could not be discovered in the usual 

 manner, but by operations made expressly for the purpose,* 



I do not pretend to determine whether the very small por- 

 tion of phosphate of lime in the Gorgonia nobilis is an essential 

 ingredient or not ; but the mode of construction evidently proves 

 how much this Gorgonia differs from the Madrepores and Mil- 

 lepores, as well as from the Gorgonia about to be mentioned. 



• Scheele's Essays, translated by Dr. Bed does. Page 208. 



