[Chas]

Dunno why they seized, no major corrosion, mouse leavings, etc.

"Early" lubricants have additives that are supposed keep the lubricant stable. But when in combination with dissimilar metals the additives react with the dissimilar metals and ruin the viscosity and become a sludge, to grease, to an organic adhesive. Some of the lubricants were organic such as whale oil, being such they can also become rancid and react in a similar manner with mixed metals.

I used to praise "Lubriplate" but in time had to go back to my own equipment and find that the lube a stiff white paste that stopped delicate mechanisms. Later I went to sewing machine oil, then 3-in-1 to motors, then Nye all purpose, thought he Nye lasted the longest, it was very temperature sensitive and on my revolver the cylinder and safety latch worked like a "slug". Later, I had problems with common mineral motor oil so dramatically changing viscosity in an oil bath filter, the filter would load the air way and choke the engine. I changed to 0-20 synthetic motor oil, perfect.
I also have Teletype machines and clocks... I used Nye's all purpose on the oily bits of the TTY machine and Nye's office machine grease "Rheolub" on the motor bearings. All is good except in cold weather the TTY machine makes errors until the "All Purpose" oil warms up.  More recently I had had more than my share of motor failures around the home, this is because of the use of "Dust-Free" cat litter, NOT. So washing out bearings and lubing with the 0-20 synthetic brings them back, In one instance I did not wash out the bearings simple saturated the wicks with the 0-20, now operating nearly a year. Oh, it is a filtered floor fan, the motor is in the filtered air...
Though I have Nye's clock oil a Horologist/radio collector is using synthetic motor oil. I followed his advice and used the synthetic oil to lube my "new" Kennenger" Grandfather clock, 3-seconds/week, perfect.
Atwater-Kent suggested using 'Nujol" a pharmaceutical mineral oil and white petroleum grease for lube in his 20's battery radios. I can only imagine it is because there are no additives to those lubricants to bugger the brass parts.
Everyone uses lubes that seem to work for them, but add the test of time like I did, the view may change...
One of the toughest "stuck" problem I had was in a Grundig receiver with a integral ball-bearing planetary drive. Stuck solid, took days of solvent soaking and heat application.
Chas