318 PHILOSOPHICAL TRANSACTIONS. [aNNO 1787. 



vessels having the appearance of a plexus of veins, some as large as a finger. On 

 exannining them, I found they were loaded with the spermaceti and oil; and that 

 some had corresponding arteries. They were most probably lymphatics; there- 

 fore I should suppose, that their contents had been absorbed from the cells of the 

 head. We may the more readily suppose this, from finding many of the cells, or 

 chambers, almost empty; and as we may reasonably believe that this animal had 

 been some time out of the seas in which it could procure proper food, it had 

 perhaps lived on the superabundance of oil. 



The solid masses are what are brought home in casks for spermaceti. I found, 

 by boiling this substance, that I could easily extract the spermaceti and oil which 

 floated on the top from the cellular membrane. When I skimmed off the oily 

 part, and let it stand to cool, I found that the spermaceti crystallized, and the 

 whole became solid ; and by laying this cake on any spongy substance, as chalk, 

 or on a hollow body, the oil drained all off, leaving the spermaceti pure and 

 white. These crystals were only attached to each other by edges, forming a 

 spongy mass; and by melting this pure spermaceti, and allowing it to crystallize, 

 it was reduced in appearance to half its bulk, the crystals being smaller, and 

 more blended, consequently less distinct. 



The spermaceti mixes readily with other oils, while it is in a fluid state, but 

 separates or crystallizes whenever it is cooled to a certain degree; like 2 different 

 salts being dissolved in water, one of which will crystallize with a less degree of 

 evaporation than the other; or, if the water is warm, and fully saturated, one 

 of the salts will crystallize sooner than the other, while the solution is cooling. 

 I wanted to see whether spermaceti mixed equally well with the expressed oils of 

 vegetables when warm, and likewise separated and crystallized when cold, and 

 on trial there seemed to be no difference. When very much diluted with the 

 oil, it is dissolved or melted by a much smaller degree of heat than when alone; 

 and this is the reason perhaps that it is in a fluid state in the living body. 



If the quantity of spermaceti be small in proportion to the other oil, it is per- 

 haps nearly in that proportion longer in crystallizing; and when it does crystallize, 

 the crystals are much smaller than those that are formed where the proportion of 

 spermaceti is greater. From the slowness with which the spermaceti crystallizes 

 when much diluted with its oil, from a considerable quantity being to be ob- 

 tained in that way, and from its continuing for years to crystallize, one would 

 be induced to think that perhaps the oil itself is converted into spermaceti. It 

 is most likely, that if we could discover the exact form of the different crystals 

 of oils, we should thence be able to ascertain both the different sorts of vege- 

 table oils, expressed and essential, and the different sorts of animal oils, much 

 better than by any other means; in the same manner as we know salts by the 

 forms into which they shoot. 



