Using a Microtome (https://en.m.wikipedia.org/wiki/Microtome).

NB: tome in Microtome has the same root as the T in CAT scan: computer aided tomography. Which is to say, slimly-sliced cabbage^W X-ray scans.

It's also the tome as in book, more properly one volume of a multi-volume (or multi-part) set, though it now generally simply means any large book.

<https://www.etymonline.com/search?q=tome>

Incredible, love learning language facts like this.

Etymology is disturbingly addictive.

https://en.wikipedia.org/wiki/Tomography: `The word tomography is derived from Ancient Greek τόμος tomos, "slice, section" and γράφω graphō, "to write" or, in this context as well, "to describe."`

The sample is stained (to make thigns visible), then embedded in a resin, then cut with a very sharp diamond knife and the slices are captured by the tape reel.

Paper: https://www.biorxiv.org/content/10.1101/2021.05.29.446289v4 See Figure 1.

The ATUM is described in more detail here https://www.eden-instruments.com/en/ex-situ-equipments/rmc-e...

and there's a bunch of nice photos and explanations here https://www.wormatlas.org/EMmethods/ATUM.htm

TL;DR this project is reaping all the benefits of the 21st century.