Biomedical Engineering Reference
In-Depth Information
of even earlier scientific events remain almost irrecoverable. This is
mainly due to a lack of the citation practice existed in the scientific
literature published in the 19
century and before.
To the best of my findings, according to Shepperd [12], as
early as in the end of the 18
th
th
century, a German chemist Martin
Heinrich Klaproth (1743-1817) and a French chemist Joseph-
Louis Proust (1754-1826) proposed that calcium phosphates were
the major inorganic component of bones. Unfortunately, Shepperd
has not provided any references to the publications by those great
chemists. However, according to Roscoe and Schorlemmer [13],
other researches had discovered this fact a bit earlier: “Gahn [14],
in 1769, discovered the existence of calcium phosphate in bones, but
it was not until this fact was published by Scheele [15] in 1771 that
phosphorus was obtained from bone-ash, which has from that time
invariably served for its preparation.” (p. 458). Furthermore, let me
cite a publication of 1777 [16] (please, note the old-fashioned using a
long, medial or descending letter “ſ”, which is a form of the minuscule
letter “s” formerly used where “s” occurred in the middle or at the
beginning of a word): “I have only been informed of this diſcovery,
by the
Gazette, Salutaire de Bouillon
, October, 1775. It is there ſaid,
that Mr.
, a phyſician at Stockholm, has communicated
a proceſs for extracting from bones the ſaline matter in question;
and that Mr.
Henry Gahn
had aſcertained, that the earth of animals was
compoſed of a calcareous ſubſtance united with the phoſphoric acid.
This diſcovery, continues the author of the article of the Gazette,
belongs to Mr.
Scheele
, and has been confirmed by later experiments."
(p. 383). Presumably, this citation might be considered as one of the
earliest mentioning on calcium phosphates.
Furthermore, as written in a book by Lavoisier [17], the
production process of orthophosphoric acid by decomposition of
calcined bones in sulfuric acid has been known since, at least, 1790
(again, the old-fashioned replacement of letter “s” by "ſ”): “The
bones of adult animals being calcined to whiteneſs, are pounded,
and paſſed through a fine ſilk ſiewe; pour upon the fine powder a
quantity of dilute ſulphuric acid, leſs than is ſufficient for diſſolving
the whole. This acid unites with the calcareous earth of the bones
into a ſulphat of lime, and the phoſphoric acid remains free in the
liquor.” (p. 205). Further, the production process of white phosphorus
has been described: “The liquid is decanted off, and the reſiduum
waſhed with boiling water; this water which has been uſed to waſh
Gahn
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