Search tips
Using boolean search:
If you are not able to find what you want using the guided search options, then you may want to try using boolean search. Many combinations of searches are possible. This section will help you get the most out of the database, whatever your interest. Experimenting will pay off!
You may wish to read the FAQ: What is in the online database? before reading further.
General principles and syntax
By default, our advanced search form searches for database items containing any of the words entered, and will also return results that are close matches. It is not case-sensitive.
In order to make your searches more specific, you may use:
- the following operators:
Operator
Description
Example
AND The boolean AND operator is used between two terms to find entries that match both origin AND species will find entries matching both origin and species OR The boolean OR operator is used between two terms to find entries that match either or both origin OR species will find entries matching either origin or species or both NOT The boolean NOT operator is used before a term to find entries that do not match that term origin NOT species will find entries matching origin but not matching species ( ) Parentheses are used to set the scope of a sub-query within a larger query. galapagos AND (finches OR birds) will find entries matching galapagos, but only if they also match finches or birds or both ” “ Double quotes can be used to encapsulate phrases to which one wishes to apply a specifier or field modifier (see below) exact:”natural selection” will only return entries containing natural selection (see below for more details of the exact: specifier) [... TO ...] The inclusive range operator will return all results within the specified range, inclusive, using lexicographical sorting. date:[1861 TO 1865] will return entries dated 1861 to 1865 inclusive, sorted lexicographically. {… TO …} The exclusive range operator will return all results within the specified range, exclusive of the endpoints of the range, using lexicographical sorting. N.B. Due to a conflict between the range operator syntax and the markup syntax used by the Darwin Correspondence Project, both online and in print, to indicate inferred dates, the exclusive range operator does not currently work with dates. surname:{quaritch TO quoy} will return entries dated with surnames between Quaritch and Quoy, but will not return entries with Quaritch or Quoy in the surname. - and/or modifiers such as:
Modifier
Description
Example
exact: the exactness specifier exact: will match only exact hits for the subsequent term, although as usual, the search will still not be case-sensitive exact:pinguicula will return entries containing pinguicula and variant capitalisations such as Pinguicula; likewise, exact:”natural selection” will only return entries containing natural selection and variant capitalisations but will not return entries containing, for instance, only such close phrases as natural and artificial selection ? The single character wildcard ? will match any single character, except at the start of a word l?g will match entries containing lag, leg, log or lug * The multiple character wildcard * will match any string of characters natural* will find entries matching natural, naturalist, naturally, etc. ~ The fuzzy modifier can be used to find entries of similar spelling to the preceding term roam~ will find entries containing roam or words of similar spelling “ … ”~xx The proximity modifier can be used to find words within a certain number of words of each other “clay loam”~10 will find entries containing clay and loam within 10 words of each other - and/or any other standard Lucene syntax queries.
- and/or field specifiers such as:
- surname:
- date:
- (N.B. The available field specifiers are described in more detail under the relevant sections below.)
- and/or table specifiers. The Darwin Correspondence Project’s online database contains different page kinds for different kinds of entry. A table within the online database stores all pages of a particular kind. By default, the search engine searches across all fields in all tables in the database, but you can restrict your search to return results only from a particular table or tables.
The drop-down menu to the right of the advanced search box permits selection of a single table from the database. If you want to restrict your search to two or more tables, use the following syntax:Search for
To find
Example
documenttype:letter Letter entries (?) documenttype:letter AND exact:”natural selection” will return only letters that contain the phrase natural selection documenttype:name Name register entries (?) (documenttype:name OR documenttype:letter) AND subject:botany will return all name register entries and letters that have been classified by the Project as bearing on the subject of botany documenttype:source Bibliography entries (?) documenttype:source AND “cambridge university press” will return only references to sources whose descriptions include the phrase cambridge university press documenttype:repdef Repository entries (?) documenttype:repdef AND “cambridge, england” will return only results for repositories in Cambridge, England
Finding letters
This section outlines how to search for letter transcriptions (or, if there are no transcriptions available, letter summaries) in the Darwin Correspondence Project’s online database.
By content
To find letters by content, select ‘Letters only
’ in the drop-down menu next to the search box, enter your search term in the box, and press, ‘Go
’. This will search all letter entry pages for your search terms.
You may additionally wish to use the body: field specifier if you want to search for terms that appear only in the historical material or editorial material (these terms are explained here) associated with a letter entry. This will eliminate results where the terms appear in the metadata for a letter entry.
Example letter content search:
body:drosera AND body:pinguicula
returns a list of letters in which both ‘drosera
’ and ‘pinguicula
’ appear in the historical or editorial material.
By correspondent
There is more than one way to find letters by correspondent. If you know the canonical name for the correspondent you are interested in (suppose it is Darwin, C. R., which is the canonical name for Charles Robert Darwin), then:
Search for |
To find |
Examples |
| author:x | letters written by x | author:”Darwin, C. R.” will return letters written by Charles Darwin |
| addressee:x | letters written to x | addressee:”Darwin, C. R.” will return letters addressed to Charles Darwin. |
However, the easiest way to find letters by or to a correspondent is first to find the biographical “name register” entry for the correspondent you are interested in; each name register entry contains links to a list of letters in the database that were sent or received by that correspondent. For tips on finding the name register entry for the correspondent you are interested in, please click here.
By date
Note: The field specifier date: is used in both the letters and name register tables to indicate the date(s) of letters and of people respectively. Therefore, if you wish to restrict your search to letters only, please select “Letters” from the drop-down list next to the search box.
The search engine interprets dates of the form YYYY-MM-DD (that is, four numbers for the year, two for the month and two for the day, with hyphens in between) from left to right. The month and day are optional, but one cannot omit the month without also omitting the day. However, one can use wildcards (see modifiers) to overcome this if desired.
Example date searches:
date:1828*
returns a list of all letters from 1828. Note the wildcard “*”. This search won’t work without it.
date:1868-03-12
returns letters dated 12th March 1868
date:18*-02-*
returns all letters written in any February
To search for a range of dates (see operators) use eg:
date:[1865-01-01 TO 1865-03-31]
By subject
Note: The field specifier subject: is used in both the letters and name register tables to indicate the subject(s) related to by letters and people respectively. Therefore, if you wish to restrict your search to letter entries only, please select “Letters only” from the drop-down list next to the search box.
Each calendar summary is indexed by subject, and these subjects can be searched for using the field specifier subject:.
The subject index is not exhaustive. It is designed to help users find the most promising matter on topics likely to be of interest and is particularly useful for cases where a simple keyword search would return unmanageably large results. For instance, searching for subject:darwin returns significantly fewer results than a search for darwin. Using subject searches like this to strip out irrelevant results, especially when combined with additional search terms, can be an excellent way to get a shortlist of letters relevant to your topic of interest.
By location
Most of the letters in the database give at least part of the address from which they were sent. These addresses can be searched for using the field specifier place:. For instance, to see all letters addressed from Down (Darwin’s home from 1842 onwards), search for place:down .
By language
To find letters by foreign language, use the field specifier physdesc: (shorthand for “physical description” of the manuscript) followed by the name of the language in straight double quotes, e.g. physdesc:”French” . The database includes letters in French, Hebrew, German, Italian, Latin, Norwegian and Spanish.
By calendar number
Every letter is identified by a unique serial number or “calendar” number assigned to it by the Darwin Correspondence Project editors. These are the numbers used in the printed versions of the Calendar to the correspondence, and in the lists of letters published at the front of each volume of the main edition of the Correspondence. To search for letters by calendar number, use the field specifier calendarnum: followed by the number (or range of numbers) you wish to search for. For instance, to find the letter with calendar number 171, search for calendarnum:171 .
By repository/provenance
To find letters by provenance, use the field specifier repository: followed by a suitable term or phrase. For instance, since all letters in the Darwin manuscript collection at Cambridge University Library have the class mark “DAR”, they may be found by searching for repository:DAR . For a list of repositories currently referenced in the online database, click here.
By published volume of the Correspondence
Note: The field specifier volume: is used in both the letters and name register tables to indicate the volume or volumes of the Correspondence in which a letter or name register entry was published. Therefore, if you wish to restrict your search to letters only, please select “Letters” from the drop-down list next to the search box.
To search for entries by the volume of the Correspondence in which they were published, use the volume: field specifier as follows:
Search for |
To find |
| volume:1 | Entries published in Volume 1 of the Correspondence. Replace the number 1 with that of the volume of your choice to retrieve entries from that volume. |
| volume:supplement | Entries published in supplements to the Correspondence. N.B. Due to legacy data issues, the online database distinguishes entries from supplements only from Volume 13 onwards. The Darwin Correspondence Project is working to rectify this issue in a future database update. |
| volume:supplement AND volume:13 | Entries published in a particular supplement to the Correspondence (in this case, the Volume 13 supplement). |
With/without images
Some letters contain images or other material that cannot be transcribed. To find letters with scans of such material, use the imagesavailable: field specifier.
Search for |
To find |
| imagesavailable:yes | Entries incorporating images. |
| imagesavailable:no | Entries not incorporating images. |
With/without transcriptions
Full transcriptions of all letters are being made available online in a rolling programme following a minimum of four years after publication in the printed edition of the Correspondence of Charles Darwin. Some additional transcriptions, selected by content matter, are being made available in advance of publication during development of special interest sections of the website.
The field specifier transcriptionavailable: can be used to search for letters with, or without, transcriptions.
Search for |
To find |
| transcriptionavailable:yes | Entries incorporating transcriptions. |
| transcriptionavailable:no | Entries not incorporating transcriptions. |
Finding people or institutions
To restrict a search to people or institutions listed in the name register, please first select “Names only” from the drop-down menu to the right of the advanced search box. If your search is unsuccessful, it may be worth performing a keyword search on the entire database as not all people and institutions are currently indexed.
By name
Each person or institution with an entry in the name register has a canonical (unique) name. In the case of people this is in the form Surname, followed by first name (where there is only one) or initials (eg. “Darwin, C. R.“). Please note that the space between initials is mandatory.
It is also possible to use the field specifiers “surname:” and “forenames:“
To find entries for Darwin’s brother, Erasmus Alvey Darwin, for example, you could search for:
surname:Darwin AND forenames:Erasmus
which returns links to entries for his grandfather, Erasmus Darwin, his son, William Erasmus Darwin, and for Erasmus Alvey Darwin, who is indexed as “Darwin, E. A.” Clicking on “Darwin, E. A.” will take you to the name register for Erasmus Alvey Darwin, which includes links to all correspondence with him, and links to all indexed references to him in the database.
The fields “title:” and “synonym:” also exist, but are not currently fully populated and searches using them are unlikely to be useful.
By gender
Name register entries may be searched for by gender with the sex: field specifier, as follows.
Search for |
To find |
| sex:male | Entries for males. |
| sex:female | Entries for females. |
| sex:unknown | Entries for people whose gender the Darwin Correspondence Project has not been able to establish. |
| sex:inappropriate | Entries for parties without gender, typically institutions such as scientific societies, commercial entities, etc., but also including mixed-gender groups of individuals, such as the entries for “Darwin family” and “Darwin children”. |
By subject
Note: The field specifier subject: is used in both the letters and name register tables to indicate the date(s) of letters and of people respectively. Therefore, if you wish to restrict your search to name register entries only, please select “Names only” from the drop-down list next to the search box.
The majority of name register entries are indexed by subject, and topics indexed are searched for using the field specifier subject:.
The subject index is not exhaustive. It is designed to help users find the most promising matter on topics likely to be of interest and is particularly useful for cases where a simple keyword search would return unmanageably large results.
For instance, searching for subject:”darwin, c. r.” returns only around half the number of results as a search for “darwin, c. r.”, because only entries about Darwin are indexed with his canonical name (”Darwin, C. R.”), whereas almost every letter in the database features his name as a correspondent.
By dates
Note: The field specifier date: is used in both the letters and name register tables to indicate the date(s) of letters and of people respectively. Therefore, if you wish to restrict your search to name register entries only, please select “Names only” from the drop-down list next to the search box.
Please note that the name register entries are not yet fully indexed by date. However, some date searching is possible within them:
Search for |
To find |
| date:1809* | Entries for people born in 1809. Replace 1809 with a different year to search for people born in that year. |
By politico-geographic origin
Please note that name register entries are not yet fully indexed by nationality. It is possible to use the field specifer nationality: combined with terms for nationalities, city or district names, but results will not be exhaustive. For example:
Search for |
To find |
| nationality:german | Entries for people, institutions or groups recorded as being German. |
| nationality:london | Entries for people, institutions or groups recorded as being from or in London. |
By occupation
Please note that name register entries are not yet fully indexed by occupation. Although the occupation: field specifier can be used, please be aware that results will not be exhaustive.
Search for |
To find |
| occupation:dentist | Entries for people, institutions or groups recorded as being dentists. |
By kind of entity
The specifiers person and society may be used as follows. Please note that results will not be exhaustive:
Search for |
To find |
| class:person | Entries for people, or groups of people not formally associated into an institution. |
| class:society | Entries for institutions. |
Finding index terms
Each letter entry and name register entry in the database is indexed. The index is not viewable as a long list of terms like an index from the back of a book; instead, the material pointed to by the index is viewable and the relevant index terms are shown alongside. Clicking on an index term retrieves a list of all database entries indexed with that term.
To search for index terms, use the subject: field specifier. There is more information on searching for letters by subject here and on searching for name register entries by subject here.
