Seven Tips for Using the Trading Consequences Database and Visualization Tools

The strengths of the Trading Consequences relational database and visualization tools lie in the information they convey about the geospatial history of particular commodities. There are a variety of ways to explore the database and visualizations. But for someone unfamiliar with the tools and the information they make available, Trading Consequences can be a bit overwhelming at first. In order to help first time users and non-specialists, here’s a list of tips to help you use the tools.

Start with a commodity, not a location. Interesting information is available for specific places, but is much more limited than the information available for specific commodities. Using location searches can be useful, but only after some initial work has been done to explore a commodity.

Tip #1 – Do a Wikipedia search

It helps to have a basic familiarity with the history of the commodity you’re searching. In most cases, if you don’t already know the basics of your commodity’s history, a Wikipedia search will provide more than enough information to get the background (where it came from, what it was used for, where it was consumed/bought).

Tip #2 – Start with the big picture

After choosing a commodity to explore, start with the Location Cloud Visualization search bar. For example, here’s the result if Ivory is entered.

Ivory main

Every location listed in the cloud is a place associated with Ivory in the entire corpus of documents. Each column represents a different decade between 1800 and 1910 (left to right). Locations are listed in alphabetical order, with the largest font representing the most frequently mentioned locations for that decade.

In this case, immediately obvious is the large number of mentions related to Havana. Your initial inclination might be to pursue what appears to be an abnormal result. But hold off on that for now!

Tip #3 – Isolate individual continents

Apart from the largest words in the cloud, it’s hard to make sense of all the information on display. To begin with, use the world map at the top of the screen to isolate the results for individual continents. Hovering the mouse over different continents will highlight locations from each continent in different colours. For example, hovering the mouse over Europe will highlight in green all the places in Europe associated with Ivory in the documents. Similarly, hovering the mouse over Africa will highlight in purple all the places in Africa associated with Ivory in the documents. Ivory Africa (hover)

Hovering the mouse over a continent will also display the total number of mentions of Ivory associated with that continent in a small text box next to the mouse (e.g. the total number of mentions for Africa is 3,137).

Actually clicking on an individual continent will control the location cloud to display only the places from that continent. For example, clicking on Africa will eliminate all locations other than places in Africa.

Ivory Africa

This will make it easier to search for patterns in the location cloud. Once you’ve finished exploring one continent, simply click on the continent again to disengage the control and return to the full location cloud. You can click on any number of continents to control for different combinations (clicking on both Europe and Africa, for example, will eliminate all other continents and display locations for places in Europe and Africa alone).

Try isolating for each continent individually as well as different combinations of continents.

Tip #4 – Isolate for specific places

It may still be difficult to identify potential patterns from the location cloud for an individual continent. Hovering the mouse over particular location names in the cloud will allow you to isolate spatial and temporal patterns. Moreover, hovering the mouse over location names in the cloud reveals the number of mentions of Ivory associated with that specific place in that decade. For example, hovering the mouse over Mozambique in the location cloud reveals there are 42 mentions of Ivory during the 1850s. More importantly, most mentions of Ivory associated with Mozambique occur during the 1840s and 1850s. Ivory Mozambique (hover)

Similarly, hovering the mouse over Zanzibar (off the coast of Tanzania) reveals there are 67 mentions of Ivory during the 1900s and that most mentions of Ivory associated with Zanzibar occur between the 1870s and the 1910s.

Ivory Zanzibar (hover)

This suggests that the ivory trade was important in Mozambique during the early nineteenth century, but that trade through Zanzibar became more important toward the end of the century.

Actually clicking on a specific location in a particular decade brings up a window display of the timeline distribution of mentions of Ivory associated with that place (normalized by all commodity/location mentions from 1800-1920), as well as a short list of selected sentences from documents that feature Ivory and that location during the decade chosen.

Ivory Zanzibar (distribution)

This visualization will give you a clearer sense of the changing trends in mentions of Ivory associated with that location (in this case Zanzibar).

Tip #5 – Explore excerpts from the documents

Once you have identified what you think are likely significant trends, it makes sense to follow up your hypothesis with a quick look through excerpts from the primary source documents in which the mentions occurred. Included in the window that pops up when you click on a specific place in one of the location cloud columns is a link to a list of documents that feature Ivory and the chosen location.

For example, clicking on the Mozambique location in 1850s column of the location cloud brings up a window with a distribution of mentions and a list of selected sentences. Clicking on the link to the full document list in the pop up window opens a new page with a list of primary source documents. By clicking on the small box next to the name of the document, you can explore the sentences that feature Ivory and Mozambique in that document. The larger the box, the more mentions that document includes.

Ivory Mozambique (docs list)

Reading through these documents allows you to determine a more accurate picture of the nature of the relationship between Ivory and Mozambique during the 1850s.

Tip #6 – Explore the other end of the commodity chain

If you started with the production end of the commodity chain (i.e. Ivory comes from Africa), try exploring the consumption side of the commodity chain (i.e. places where Ivory ended up).

Instead of isolating Africa, try isolating Europe or North America. Look for similar types of patterns using the same methods described above and then follow up with the primary sources by clicking on promising-looking specific locations on the location cloud.

For example, isolating Europe in the location cloud reveals a high number of mentions associated with Lisbon (Portugal) earlier in the nineteenth century,

Ivory Lisbon (distribution)


followed by a rise in the number of mentions associated with Germany toward the end of the century.

Ivory Germany (distribution)

During the nineteenth century, Mozambique was a Portuguese colony and Germany held imperial interests (along with Britain) in Zanzibar. The patterns of mentions of Ivory in Europe, therefore, suggest a strong correlation with the patterns of mentions of Ivory associated with Africa.

Indeed a quick reading of excerpts from the documents confirms this to be the case.

In this list of documents from the 1850s, Lisbon is mentioned in relation to Mozambique and Ivory several times.

Ivory Lisbon (docs list)

Similarly, an 1888 document dealing with relations between Germany and Zanzibar mentions Ivory as a commodity key to peace negotiations.

Ivory Germany (docs list)

Tip #7 – Cross-reference with a full corpus commodity search

A separate Commodity search bar allows you to cross-reference the information obtained from your exploration of the commodity-location patterns in the Location Cloud Visualization.

For example, here’s the result if Ivory is entered.

Ivory commodity search

The list on the right contains all the documents in which Ivory is mentioned (use the ‘next’ button at the bottom to advance to the next page). This list can be narrowed down into ten year blocks by clicking on a specific decade at the bottom left (the number in brackets next to each decade denotes the number of mentions of Ivory in that decade).

Hopefully these tips will help get you started using the database and visualization tools. Trading Consequences is a great resource with a lot to offer anyone interested in global commodity flows during the nineteenth century. To use these tools effectively, however, requires several sessions in between which users must be spend time reading through the literature to confirm results and determine new avenues of enquiry to guide further use of Trading Consequences.

Official Launch of Trading Consequences!

Today we are delighted to officially announce the launch of Trading Consequences!

Over the course of the last two years the project team have been hard at work to use text mining, traditional and innovative historical research methods, and visualization techniques, to turn digitized nineteenth century papers and trading records (and their OCR’d text) into a unique database of commodities and engaging visualization and search interfaces to explore that data.

Today we launch the database, searches and visualization tools alongside the Trading Consequences White Paper, which charts our work on the project including technical approaches, some of the challenges we faced, and what and how we have achieved during the project. The White Paper also discusses, in detail, how we built the tools we are launching today and is therefore an essential point of reference for those wanting to better understand how data is presented in our interfaces, how these interfaces came to be, and how you might best use and interpret the data shared in these resources in your own historical research.

Find the Trading Consequences searches, visualizations and code via the panel on the top right hand side of the project website (outlined in orange).

Find the Trading Consequences searches, visualizations and code via the panel on the top right hand side of the project website (outlined in orange).

There are four ways to explore the Trading Consequences database:

  1. Commodity Search. This performs a search of the database table of unique commodities, for commodities beginning with the search term entered. The returned list of commodities is sorted by two criteria (1) whether the commodity is a “commodity concept” (where any one of several unique names known to be used for the same commodity returns aggregated data for that commodity); or (2) alphabetically. Read more here.
  2. Location SearchThis performs a search of the database table of unique locations, for locations beginning with the search term entered. The returned list of locations is sorted by the frequency that the search term is mentioned within the historical documents. Selecting a location displays: information about the location such as which country it is within, population etc; A map highlighting the location with a map marker; A list of historical documents and an indication of how many times the selected location is mentioned within each document. Read more here.
  3. Location Cloud Visualization. This shows the relation between a selected commodity and its related location. The visualization is based on over 170000 documents from digital historical archives (see list of archives below).The purpose of the visualization is to provide a general overview of how the importance of location mentions in relation to a particular commodity changed between 1800 and 1920. Read more here.
  4. Interlinked Visualization. This provides a general overview of how commodities were discussed between 1750 and 1950 along geographic and temporal dimensions. They provide an overview of commodity and location mentions extracted from 179000 historic documents (extracted from the digital archive listed below). Read more here.

Please do try out these tools (please note that the two visualizations will only work with newer versions of the Chrome Browserand let us know what you think – we would love to know what other information or support might be useful, what feedback you have for the project team, how you think you might be able to use these tools in your own research.

Image of the Start page of the Interlinked Visualization.

Start page of the Interlinked Visualization.

We are also very pleased to announce that we are sharing some of the code and resources behind Trading Consequences via GitHub. This includes a range of Lexical Resources that we think historians and those undertaking historical text mining in related areas, may find particularly useful: the base lexicon of commodities created by hand for this project; the Trading Consequences SKOS ontology; and an aggregated gazeteer of ports and cities with ports.

Bea Alex shares text mining progress with the team at an early Trading Consequences meeting.

Bea Alex shares text mining progress with the team at an early Trading Consequences meeting.


The Trading Consequences team would like to acknowledge and thank the project partners, funders and data providers that have made this work possible. We would particularly like to thank the Digging Into Data Challenge, and the international partners and funders of DiD, for making this fun, challenging and highly collaborative transatlantic project possible. We have hugely enjoyed working together and we have learned a great deal from the interdisciplinary and international exchanges that has been so central to to this project.

We would also like to extend our thanks to all of those who have supported the project over the last few years with help, advice, opportunities to present and share our work, publicity for events and blog posts. Most of all we would like to thank all of those members of the historical research community who generously gave their time and perspectives to our historians, to our text mining experts, and particularly to our visualization experts to help us ensure that what we have created in this project meets genuine research needs and may have application in a range of historical research contexts.

Image of the Trading Consequences Project Team at our original kick off meeting.

Image of the Trading Consequences Project Team at our original kick off meeting.

What next?
Trading Consequences does not come to an end with this launch. Now that the search and visualization tools are live – and open for anyone to use freely on the web – our historians Professor Colin Coates (York University, Canada) and Dr Jim Clifford (University of Saskatchewan) will be continuing their research. We will continue to share their findings on historical trading patterns, and environmental history, via the Trading Consequences blog.

Over the coming months we will be continuing to update our publications page with the latest research and dissemination associated with the project, and we will also be sharing additional resources associated with the project via GitHub, so please do continue to keep an eye on this website for key updates and links to resources.

We value and welcome your feedback on the visualizations, search interfaces, the database, or any other aspect of the project, website or White Paper at any point. Indeed, if you do find Trading Consequences useful in your own research we would particularly encourage you to get in touch with us (via the comments here, or via Twitter) and consider writing a guest post for the blog. We also welcome mentions of the project or website in your own publications and we are happy to help you to publicize these.

Image of Testing and feedback at CHESS'13.

Testing and feedback at CHESS’13.

Explore Trading Consequences

Comparing Apples with Oranges

This Friday we will officially launch Trading Consequences this Friday (21st March), with publication of our White Paper and the launch of our visualization and search tools. Ahead of the launch we wanted to give you some idea of what you will be able to access, what you might want to view and what you might want to compare with these new historical research tools. Professor Colin Coates has been exploring the possibilities… 

The “Trading Consequences” website literally allows us to compare apples and oranges.  Both fruits became the objects of substantial international trade in the nineteenth century, as in the right conditions they can remain edible despite being shipped great distances.

Screen shot of a visualisation of Apple Trades

They are complementary fruits in many ways, as apples are grown in temperate climates whilst oranges prefer warmer conditions.  They may overlap geographically, but typically we associate different parts of the world with each fruit.  In the context of the British world, apples grew in the United Kingdom, of course, but they also came from Canada, New Zealand and the United States, among other locations.  Oranges from places like Spain, Florida or Latin America entered the United Kingdom in the nineteenth century.  The two maps which result from entering “apple” and “orange” into the database show, at a glance, how oranges appeared more often in reference to warmer zones than apples.

Screen shot of a visualisation of Orange Trades

The chronological distribution of commodity mentions was roughly similar in both cases.  Increased attention from 1880 to 1900 reflects in part the expansion of the documentation in that period, but it likely also reflected growth in trade and consumption.  Historian James Murton has pointed out that regular trade in apples developed from Canada to Great Britain in the 1880s, focused primarily in Nova Scotia.  On average, one million bushels of apples reached British markets (Murton, 2012).

In contrast, both apples and oranges show sudden spikes in the 1830s, for entirely different reasons.  The spike for apples points the researcher to a useful “Report from the Selection Committee on the Fresh Fruit Trade” in 1839.  But the mid-1830s spike in oranges points instead to the activities of Orange Lodges in Ireland.  The other visualisation shows this anomaly even more clearly, as IRELAND takes on a prominence in related geographical terms in the 1830s that it did not occupy afterwards.

Screenshot of Visualisation looking at trades in the 1830s

This project entailed teaching computers to read as an historian might, and there are distinct advantages to being able to deal with such a wide range of documentation.  However, all historians must be critical of the sources we use. The visualisations in “Trading Consequences” point towards useful sources for further study, and to suggest that historian may wish to consider some regions in their analysis.  The importance of the United States in the discussions about apples is noteworthy, for instance.  Australia has a large number of mentions of oranges, though it is important to note that a small city boasts the same name and could account for part of the number.  (Interestingly enough, Orange, New South Wales, did not grow many oranges according to the Australian Atlas 2006! But it does have apples.)

"Fruit" by Flickr user Garry Knight / garryknight

“Fruit” by Flickr user Garry Knight / garryknight

The increase in mentions of both apples and oranges from the 1880s on may reflect improving living standards in Britain in that period.  Britain’s decision to adopt free trade had led to an increase in a wide variety of imported foodstuffs (Darwin, 2009).  As the heightened attention to both apples and oranges probably shows, these fruits were part of that movement.

The “Trading Consequences” visualisations show some instructive comparisons, some that may point to different ways to conceive of trade in these resources, and others which illustrate the care with which researchers should approach results.


  • John Darwin, The Empire Project: The Rise and Fall of the British World-System, 1830-1970 (Cambridge: Cambridge University Press, 2009)
  •  James Murton, “John Bull and Sons: The Empire Marketing Board and the Creation of a British Imperial Food System” in Franca Iacovetta et al., eds., Edible Histories, Cultural Politics: Towards a Canadian Food History (Toronto: University of Toronto Press, 2012), 234-35.
  • New South Wales Government, Agriculture – Fruit and Vegetables in the Atlas of New South Wales, Available from: