Fascinating! I had heard the term "Linotype" many times, but never saw what it was. Amazing how advanced that technology must have been at the time, and to have justification? Brilliant!

The clickity-clack Steampunk wow factor on this is off the charts. Mergenthaler was apprenticed to a watchmaker in Germany so he had a fluency for all this fine mechanical precision (somebody bring apprenticeships back). He was tasked to do this by the legal industry, which has to have at least four copies of everything (as Richard Nixon said, you need a cast iron behind to be a lawyer, looooot of reading). Newspapers ran with it, design was a mainstay for a century. The modern air conditioner also came out of the printing industry when Sackett-Wilhelms Lithographing & Publishing Company in Brooklyn hired Willis Carrier to remove the humidity in the cavernous printing plant that was causing paper to shrink and swell (and it is HOT in NYC in the summer). Somebody noticed "Hey, it feels really good in here" and Willis installed a version of his "chiller" machine in movie theaters, it took off from there. America baby.

Ever used one with a gas heated pot? I have. Linotype / Intertype horrible to use if the distributor keeps jamming or the magazine is dirty inside; or you forget to set the right ejector to push the slug out of the mould. :)

It's not actually lead, it's type metal which is an alloy of lead, tin and antimony.