Note 55 bis — Chapter XX · SULPHUR, SELENIUM, AND TELLURIUM

Whether similar (even small) breaks in the continuity of the factor dS/dp exist or not, for other hydrates (for instance, for H2SO4H2O and H2SO44H2O) cannot as yet be affirmed owing to the want of accurate data (Note 53). In my investigation of this subject (1887) I admit their possibility, but only conditionally; and now, without insisting upon a similar opinion, I only hold to the existence of a distinct break in the factor at H2SO4, being guided by C. Winkler's observations ond the specific gravities of fuming sulphuric acid.