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Scholars from non-profit institutions of higher education are eligible to use the HTRC Data Capsule. First, make an account for the HTRC Portal, and once logged in, you can set up a capsule for yourself.

I am from


the private sector, can I sign up an account to use the Data Capsule? 

 Unfortunately not. Our use policy limits access to only users from most academic institutions.

Is there a tutorial for Data Capsule?

Yes, we have written a step-by-step HTRC Data Capsule tutorial you might find useful.

Where can I use Data Capsule?


Setting up your HTRC Data Capsule 

The HTRC Portal showed an error message when I tried to create a Data Capsule. What went wrong?

Most likely the number of capsules on our server has reached its limit. Please contact HTRC support to solve the issue:

How many total Data Capsules can the HTRC support at one time? How many can I check out?

We offer 15 capsules for scholars to check out. In other words, 15 Data Capsules can exist in our system at any one time. While there is no limit on how many capsules a single user can check out, we strongly suggest each user check out only one capsule at a time out of consideration for the wider user community.

I want to create a Virtual Machine (capsule) with several Virtual CPUs (VCPUs). Is there an upper limit to the number of Virtual CPUs that I can create?

Each user is allowed to use up to 10 VCPUs. If you find that you tried to create a capsule with less than ten VCPUs but the attempt failed, then it is possible that you may have already used up your quota of 10 in an existing capsule. 

Using your HTRC Data Capsule

Can I ssh ("secure-shell") into an HTRC Data Capsule?     

You can ssh into your capsule when it is in maintenance mode only. (See below to learn more about Maintenance and Secure Modes.)


The link for downloading results, which is sent to the user by email, will be good for 12 hours after the email is sent.  After that, the results can no longer be downloaded.

Can I import the workset that I created in the HTRC Portal into the HTRC Data Capsule?

Currently, the best way to do this is to download the workset from the Portal, which will export a list of the volume IDs for that workset, and then use the HTRC Data API in the Data Capsule to access the content in those volumes. It is not presently possible to export a workset from the Portal directly into the HTRC Data Capsule, but we expect to integrate this functionality into future versions.

I have some Python scripts that I want to use in my analysis within the HTRC Data Capsule. How should I start?

  • First store your Python scripts somewhere on Internet. 
  • Start your capsule from within the Portal, and make sure your machine is in maintenance mode.
  • Log into your capsule from a VNC client.
  • Download the Python scripts from the Internet onto your capsule.
  • Switch to secure mode. 
  • If you know the volume IDs that you are interested, you can go ahead to fetch content of these volumes by using this sample Python script in Fetching Volume OCR Content in HTRC Data Capsule (Secure Mode)
  • Run your Python scripts agains the content.
  • If you don't have the volume IDs of your interest, you can search for volumes along with their ID via the HTRC Solr search engine. You can search by subject, topic, author, year, etc., and identify the volumes of interest and record their volume IDs from Solr search results. The HTRC Solr search API is a RESTFUL web service which you can call in a capsule's secure or maintenance mode. Instructions on how to use HTRC Solr API can be found at Solr Proxy API User Guide (archive).
  •  Alternatively, you can build a work set from the HTRC Portal and Workset Builder and obtain the volume IDs of your workset from the Portal. 
  • Once you have the volume IDs ready, you can go ahead to fetch the volume content in Data Capsule secure mode and perform analysis using your Python scripts as mentioned above.


Where can I receive announcements and updates about HTRC Data Capsule?

  1. Check the HTRC Data Capsule documentation pages from time-to-time.
  2. Subscribe to our user group list htrc-usergroup-l @ to receive most recent announcements and updates about the HTRC Data Capsule as well as other services.

Still have questions?

Please contact HTRC support at, and one of our team members will reply to your questions.