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HISTORICAL VIEW OP THE

constitutes a latent process of a very complex kind. Thelatent schematism is that invisible structure of bodies onwhich so many of their properties depend ; as the struc-ture of crystals, &c.; or that arrangement of particlesby which the peculiar constitution of matter in regardto elasticity, magnetism, &c. is determined.

In pursuing the enquiry after the “ forms” of phe-nomena, the first step is to see what forms must, fromthe nature of the case, be excluded. This limits thefield of hypothesis, and brings the enquiry within anarrower compass. Thus, if we were enquiring intothat quality which is the cause or form of transpa-rency, we must at once exclude rarity or porosity, be-cause in the diamond we have an instance of a verydense body which is also transparent. There is alsogreat importance in attending to negative instances, asglass when pounded is not transparent. After a greatnumber of exclusions have left but a few principlescommon to every case, one of these may be assumed asthe cause, and the validity of the assumption tried, byreasoning from it hypothetically, to see whether it willaccount for all the phenomena. “ To man,” the au-thor observes, “ it is only given to proceed at first bynegatives, and in the last place to end in an affirmativeafter the exclusion of every thing else.” He gives anadmirable exemplification of his method by taking thesubject of heat, and going through the process recom-mended, as far as the then state of knowledge wouldpermit.

In the process of inductive enquiry thus pursued, itcould not but occur that some facts would be found ofmuch more importance than others to the discovery ofthe truth. Some of them show the thing sought in itshighest, others in its lowest degree: some exhibit itsimple and uncombined ; in others it appears confusedwith a variety of circumstances. Some facts are easilyinterpreted; others very obscure, and are understoodonly in consequence of the light thrown upon them bythe former. These differences led Bacon to distinguish