- hardening into occlusive onsets:
- vocalization of the first semivowel, its addition to a diphthong, and division of the diphthong and remaining semivowel into two separate segments in West Germanic.
The process is brought about by the fact that vowels (or semivowels) in the syllable margin are invariably transformed into consonantal articulations.
The conditions of the sound change were long debated, since there was a seemingly random distribution of affected and unaffected words. At first, dependence on word accent was assumed, parallel to Verner's Law. One currently accepted solution, first proposed by Smith (1941), postulates dependency on the presence of a PIE laryngeal, which when lost, triggered lengthening as if the semivowels were vowels, and forced them into the syllable margin.
According to Lehmann (1955), the lengthening occurs in the contexts of PIE * -VwH-, * -iyH-, * -ayH-, * -aHy- (where V is any short vowel, and H is any laryngeal).
For example, PIE *drewh₂yo → early Proto-Germanic *trewwjaz "trustworthy, faithful" →:
- *triwwjaz: Old Norse tryggr, Gothic triggws
- *triuwjaz: Old English trēowe, Old High German gitriuwi.
One instance where a laryngeal was never present is PIE *h₂ōwyóm "egg", but after the loss of * -w-, the * -y- shifted into the syllable margin, giving:
- with hardening:
- *ajjis: Crimean Gothic ada (pl.) (*addi (sg.) < *ajjis)
- *ajjaN: Old Norse egg
- with diphthongization:
- *aijaz: German Ei, Old English ǣġ
Some linguists (e.g. Joseph Voyles) hold that Holtzmann's Law represents two separate and independent sound changes, one applying to Gothic and another to Old Norse, rather than being a common innovation. This is supported by James Marchand's observation that a Runic inscription (niuwila on the Naesbjaerg bracteate of the 5th century) and an early loan into Finnic (*kuva "picture", cf. Gothic skuggwa "mirror", Old High German skūwo "look") do not exhibit this change. If true, this would prevent Holtzmann's law being used as an example of early Gotho-Nordic unity, in which context it is often cited. Voyles's explanations of the changes do not involve laryngeal theory.
- Natalie Operstein, Consonantal Structure and Prevocalization (John Benjamins, 2010), 91.
- Henry Lee Smith, Jr., The Verschärfung in Germanic, Language 17 (1941), 93-9.
- Winfred P. Lehmann, Proto-Indo-European Phonology (1955), chapter 4: 'Lengthened /w/ and /y/ in the Gmc. Dialects'
- The plurals OHG eigir and OE ǣgru exhibit an s-stem; .
- Joseph B. Voyles, Early Germanic Grammar (San Diego: Harcourt Brace, 1992), 25-6.
- James Marchand, The Sounds and Phonemes of Wulfila's Gothic, The Hague: Mouton (1973), 87.
- William M. Austin, Germanic Reflexes of Indo-European -Hy- and -Hw-, Language (1958), 203-211.
- L. C. Smith, What's all the fuss about 16 words? A new approach to Holtzmann's law Göttinger Beiträge zur Sprachwissenschaft 1.
- L. C. Smith, Holtzmann's law: getting to the hart of the Germanic verscharfung, University of Calgary thesis, ISBN 0-612-24623-X (1997).