The digestion and assimilation of fat in the human body : an epitome of laboratory notes on physiological and chemical experiments bearing on this subject / by H. Critchett Bartlett.

  • Bartlett, H. Critchett (Henry Critchett)
Date:
1877
Catalogue details

Licence: Public Domain Mark

Credit: The digestion and assimilation of fat in the human body : an epitome of laboratory notes on physiological and chemical experiments bearing on this subject / by H. Critchett Bartlett. Source: Wellcome Collection.

    18/48 (page 18)
    solution. This may be filtered off, and evaporated at a low temperature. The latter separation produces with certainty an almost colourless powder, absolutely inert as a solvent of fibrin, but a powerful starch converter. I greatly prefer the use of pyroxylin for the isolation of this particular principle, for I must confess I failed to reach this result by means of the nitrated starch. If this method of analysis can be extended by redis¬ solving the double precipitate, so that the fibrin-solvent is obtainable from a mixture of ether and water, it will greatly add to the value of the process, supposing we I need not depend upon excessive nicety of manipulation, j According to my own experience, however, I prefer ex¬ tracting the fibrin-solvent free from the starch-transform¬ ing principle and all other extraneous matter by pre¬ cipitating with calcic phosphate, which can be readily conducted with the necessary accuracy. A naturally neutral watery extract should be taken from the gland; that is to say, the usual alkaline extract is allowed to stand until it has become exactly neutral. Sufficient tri-basic phosphoric acid is thrown in to make up the whole to a solution of one in twenty. It is then slightly over-neutralized with a known quantity of lime in water; to which the precise equivalent of phosphoric acid is added to produce an insoluble bi-calcic phos¬ phate, from which the fibrin-solvent can be washed with distilled water. Other methods of isolating these two active principles give results similar in all essentials to the solvents yielded by the foregoing analytical processes. The sub¬ stantial truth of the propositions involved is thus con¬ firmed, and we can now class these peculiar agents and their reactions as known principles, producing well-defined