This paper reports on the mechanical strength of highly porous ceramics in terms of the Weibull and Duxbury-Leath distributions. More than 1000 side-crushing strength tests on silica-catalyst carriers of various particle sizes have been performed in series. Within a series, preparation conditions were kept constant. Analysis of the fluctuations of the failure pressure around its expectation value proves that the length dependence of the mechanical strength is well described by both distributions. Focusing upon the failure pressure dependence, the mu = 1 Duxbury-Leath distribution appears to be the more appropriate.