I must, however, acknowledge that the last words of Pliny I do not fully comprehend. They have not indeed been noticed by any commentator; but I do not on that account believe that I am the only person to whom they have been in part unintelligible. Savot and Watson[530], who were undoubtedly capable of giving some decisive opinion on them, have purposely left that part, which to me appears obscure, untranslated and without any explanation. Pliny says, “Improbiores ad tertiarium additis æquis partibus albi, argentarium vocant, et eo quæ volunt, incoquunt.” He seems here to throw out a reproach against those who melted together equal quantities of _tertiarium_ and pure tin, and then gave it the name of _argentarium_, as if it had been of an inferior quality to the _argentarium_ first named. But equal quantities of _tertiarium_ and pure tin produced a mixture, in which for _one_ part of lead there were _two_ of tin. How then could those who made this mixture be called _improbiores_? To answer this question I shall venture to give my conjecture. Pliny perhaps meant to say, that tinning properly ought to be done with pure tin, but that unprincipled artists employed for that purpose tin mixed with lead. If this be the true meaning, his reproach was not unfounded. On the same account, because all tin was then adulterated with lead, Galen gives cautions against the use of tinned vessels, and advises people to preserve medicines rather in glass or in golden vessels. But why does Pliny add, “ideo album nulli rei sine mixtura utile?” In using these words, it is possible he may have alluded, not to tinning, but to things cast of tin, which, according to the ideas of that time or the nature of the tin, if of that metal alone, would be too brittle. This seems to be said by the preceding words, to which the _ideo_ refers: “albi natura plus aridi habet, contraque nigri tota humida est, ideo album....” I hope the reader will forgive me for entering so deeply into criticism; but if Pliny’s valuable work is ever to become intelligible, occasional contributions of this kind must not be despised.