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Blagden, Sir Charles (1748-1820)

Identity Statement

Reference code(s): GB 0117 CB
Held at: Royal Society
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Full title: Blagden, Sir Charles (1748-1820)
Date(s): 1771-1820
Level of description: Collection (fonds)
Extent: 41 volumes and 15 boxes
Name of creator(s): Blagden | Sir | Charles | 1748-1820 | Knight | physician


Administrative/Biographical history:

Blagden was born at Wotton-Under-Edge, Gloucestershire. He studied medicine at Edinburgh and received his M.D. in 1768. He was elected FRS in 1772 and served as a medical officer in the British Army from about 1776 to 1780. He was Henry Cavendish's assistant from 1782 to 1789, from whom he received an annuity and a considerable legacy. Blagden succeeded Paul Henry Maty as Secretary of the Royal Society in 1784 (while the Society was divided over the efficacy of its President, Sir Joseph Banks, a close friend of Blagden's), serving until 1797. Both in this capacity and as Cavendish's assistant he became involved in the prolonged 'water controversy' - who had priority in discovering the composition of water, claimed by both Cavendish and James Watt in England and A L Lavoisier in France. Blagden admitted responsibility for conveying, quite well-meaningly, word of the experiments and conclusions of both Cavendish and Watt to Lavoisier; and he overlooked errors of date in the printing of Cavendish's and Watt's papers. His experiments on the effects of dissolved substances on the freezing point of water led to what became known as 'Blagden's Law', where he concluded that salt lowers the freezing point of water in the simple inverse ratio of the proportion the water bears to it in the solution. In fact Richard Watson had first discovered the relationship in 1771. Blagden spent much of his time in Europe, particularly in France, where he had many friends among French scientists such as C L Berthollet. He died in Arcueil in 1820. He was knighted in 1792.


Scope and content/abstract:

The correspondence, papers and diaries of Sir Charles Blagden. Blagden's papers are interesting on several levels, generally for his close contact with European men of learning, and his relationship with Sir Joseph Banks. Blagden's professional researches are represented by medical notes in the boxed sequence. These are grouped with papers on other subject interests, including linguistics, e.g. a draft Tahitian-English dictionary, compiled from conversations with Omai, whom Blagden inoculated after Omai's voyage to England with James Cook. Blagden's interest in antiquities and travel is documented by diary entries, as is his intercourse with fellow scientists, particularly those associated with the founding of the Royal Institution.

Access & Use

Language/scripts of material:
English and Tahitian

System of arrangement:

Conditions governing access:

Only those parts of the collection which have been listed are accessible.

Conditions governing reproduction:

No publication without written permission. Apply to Archivist in the first instance.

Finding aids:

Blagden's copy letter-book (BLA.7) is the only volume of the series to contain an index. There is a separate card index to the remaining letter-volumes stored with the collection; the information here is duplicated in the General Card Cataogue, i.e. author, address, date, recipient, and reference number. Blagden's own letters in draft and copy form are not recorded in the General Card Catalogue. Boxed papers have abbreviated listings in each box; the diary is unindexed. Printed volumes are noted in the Society's catalogue of printed material. Two boxes received in 2000 are unsorted.

Archival Information

Archival history:

Immediate source of acquisition:

Purchased by the Royal Society in 1947. A further two boxes were purchased for 2,000 from the Fairhurst estate in 2000.

Allied Materials

Related material:

Beinecke Library, Yale University Library, holds correspondence and papers covering 1770-1820 (c1100 items); Wellcome Library for the History and Understanding of Medicine holds papers covering 1767-1780; Gloucestershire Record Office holds correspondence and papers covering 1775-1819; Fitzwilliam Museum, Cambridge University, holds 75 letters to Sir Joseph Banks, 1773-1805; Royal Astronomical Society Library holds correspondence with Sir William Herschel, 1781-1814; Sedgwick Museum of Geology, Cambridge University, holds 17 letters to Edward King; Huntington Library holds 30 letters to Elizabeth Montague.

National Register of Archives: Click here to view NRA record

Publication note:

Description Notes

Archivist's note:
Description produced by the Royal Society and revised by Rachel Kemsley as part of the RSLP AIM25 project.

Rules or conventions:
Compiled in compliance with General International Standard Archival Description, ISAD(G), second edition, 2000; National Council on Archives Rules for the Construction of Personal, Place and Corporate Names, 1997.

Date(s) of descriptions:
Created 2/11/2001, modified 17/06/2002, revised Sep 2002

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