My new favorite book.
Published in 1868!
400 pages of comparative goodness.
Verb conjugations (we really should bring back thou hadst and the T-V distinction in English!)
There’s even vocabulary at the end, though the words are not grouped thematically like they are in The Loom of Language.
I’ve also ordered A Comparative Practical Grammar of French, Italian and Spanish by Oliver Heatwole (1949) as well as Comprendre les langues romaines: Du français à l’espagnol, au portugais, à l’italien & au roumain by Paul Teyssier (2004), but I haven’t yet found a book like this for the Germanic languages. As soon as I can determine if Notley’s book is in the public domain (there was a reprint in 1977 by an American publisher), I will start scanning and/or re-typing it to share it online.