A note for my Finnish-proficient readers and other interested people: I’ve transcribed and uploaded Arvid Genetz’ presentation Suomalais-ugrilainen đ ensimmäisen ja toisen tavuun vokaalien välissä (published 1896) on Wikisource.
This is one of the three works to have come from Finland in the mid-1890s where people seemed to discover just about in parallel that no, original *t does not become Hungarian /l/, and that an entirely different proto-consonant needs to be set up instead for words like Hu. elő ~ Finnish ete- ‘fore, front’; Hu. tele ~ Fi. täyte- ‘full’. A nice demonstration of the internal consistency of the comparative method.
Genetz here does not manage to distinguish the plain and palatal variants *d₁, *d₂ though; that detail would be instead proposed by his more famous student E. N. Setälä.
It’s an interesting read from a 21st century perspective. Plenty of standard etymologies are already in place. There however remain several etymological comparisons that I can only describe as pre-scientific (e.g. Hungarian bűz ‘to smell’ ~ Finnish mätä ‘rotten’). Others yet look like they might be onto something, but seem to have remained without further investigation over the last dozen decades, e.g. an analysis of Fi. hiukka ‘small amount’ as a deminutive of hitu ‘thin bit, flake’.
The Finnish of the times is interesting to read, too. Dated enough to be obviously old, but still perfectly understandable. Perhaps the strangest thing might be a detail of Genetz’ phonetic terminology: he describes /ð/ as alveolaarinen vs. Hungarian /z/ as dentaalinen, the exact opposite from what we’d expect today.