Reletter
Artwork for Res Obscura

Res Obscura

Benjamin Breen
Tens of paid subscribers

Notes on the history of technology, medicine, science, art, drugs, and empire. Also: AI in research and teaching.

Platform
Substack
PricingOnly free issuesPublishesWeekly
Issues60Founded3 years agoLast Issue11 days ago
Active

Read this Newsletter

resobscura.substack.com
Artwork for Res Obscura

Latest Issues

Using Opus 5.5 to discover a new eyewitness record of the dodo

Another day, another historical cipher broken by a frontier model. Yesterday, the security researcher Carter Church announced that he had used GPT-6 Astra (working on the problem for six hours) to break a Napoleonic-era cipher that had prev...

11 days ago
34
15

AI labs need to start funding historical research

I’ve written previously about the pitfalls and use cases for AI in augmenting historical research, but things have changed significantly since 2024-25. Occasioned by the dueling releases of GPT-6 Sol and Opus 5.5 this week, I thought I’d sh...

18 days ago
68
16

The "mechanical miracle" that ruined Mark Twain's life

“All the other wonderful inventions of the human brain sink pretty nearly into commonplaces contrasted with this awful mechanical miracle.”

Such was Mark Twain’s verdict on the Paige Compositor, a typesetting device which was among the mos...

2 months ago
43
5

Quality non-fiction books are the antithesis of AI slop

My first year of college, I had a work-study job which ended up being one of the most sneakily important intellectual experiences of my life. I was a lowly library shelver, assigned to the shelves labelled A through F section in the Library...

3 months ago
114
24

What is happening to publishing?

The big news in the world of writing today is the controversy over the award of a Commonwealth Foundation Short Story Prize to a story called “The Serpent in the Grove.” The piece was almost certainly co-authored by AI.

As of this morning...

5 months ago
47
16

Key Facts

Contact Information
Newsletter Author
Number of Subscribers
Find out how many people subscribe to this newsletter.

Audience Metrics

Subscribers, engagement, traffic and sponsorship for Res Obscura.

SubscribersEngagement77Monthly Web Visits
Accepts SponsorsEstimated Cost per Ad

SEO Reach

Where Res Obscura ranks on Google, and how much search traffic it brings in.

Ranked Keywords2.1kMonthly Search TrafficTop Keywords

Chart Rankings

How this newsletter ranks in the official Substack charts.

#113
Substack
/History(Free)
#189
Substack
/History(Paid)

Authors

The writers behind this newsletter.

  • Benjamin Breen

    Historian of science, medicine, technology, drugs, and culture at UCSC.

  • Frequently Asked Questions

    How can I access the email archive for Res Obscura?

    You can find recent issues that have been published by Res Obscura on Reletter by scrolling up to where it says Latest Issues. Tap on the link for any of the most recent emails or hit More Issues to see older ones.

    How many subscribers does Res Obscura have?

    To see how many people subscribe to Res Obscura, simply upgrade your Reletter account. We provide readership numbers and lots of other stats for this newsletter so you can decide if it's worth reaching out to.

    How can I advertise in Res Obscura?

    Newsletter advertising can be extremely effective when it's done right. Before you pitch Res Obscura as a potential sponsor or partner, make sure that you've done your research and checked its newsletter stats with Reletter.

    Then, personalize one of our winning pitching templates and send it to the right person using the contact info provided.

    How much does it cost to sponsor a publication like Res Obscura?

    Newsletter ad rates (or CPM) vary depending on many factors, including industry, number of subscribers, open rate, ad placement and more.

    To find out how much an ad will cost, contact Res Obscura using the contact information provided and ask for a copy of their media kit.

    How can I find newsletters related to Res Obscura?

    Scroll up to where it says Related Newsletters to see other publications like Res Obscura. You can also search our email newsletter directory to discover other newsletters that cover the topics you're interested in.

    How do I contact Res Obscura?

    Reletter provides this newsletter's website URL above, where you will often find their contact information. We also provide links to associated social media accounts and pitching templates so you can reach out fast.