The interaction of water with the silica surface is explored using *H NMR techniques. The silica is examined at various levels of hydration/dehydration and temperature, using line narrowing by magic-angle spinning, with or without multiple-pulse averaging ofdipolar interactions. Water physisorbed on the silica surface exhibits a freezing point depression of roughly 40 K. Molecular reorientation of physisorbed water at rates in the tens of kilohertz range is observed through interference with multiple-pulse line narrowing. These results are correlated with variabletemperature NMR spectra of pure water. Isotropic

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A13C CP/MAS NMR study of furfuryl alcohol resins is reported. A conformational rigidity is found for uncured or less cured resins. The contents of methylol groups and dimethylene ether linkages are found to be very small. It is postulated that cross-linking involves the breaking of methylene bridges in the curing process. Further confirmation is given that the major cross-linking processes that occur during curing involve linkages with bridging CH2 groups, rather than substitution at the 3-and 4-positions of furan rings in the resins.