BOOK II.] INSTANCES OF THE ROAD. 525 



XLI. In the eigliteentli rank of prerojrative instances we will 

 class the instances of the road, which we are also wont to call 

 itinerant and jointed instances. They are such as indicate the 

 gradually continued motions of nature. This species of in- 

 stances escapes rather our observation than our senses j for men 

 are wonderfully indolent upon this subject, consulting nature in 

 a desultory manner, and at periodic intervals, when bodies have 

 been regularly finished and completed, and not during her work. 

 But if any one were desirous of examining and contemplating 

 the talents and industry of an artificer, he would not merely 

 wi^h to see the rude materials of his art, and then his Avork 

 ^hen finished, but rather to be present whilst he is at labour, 

 and proceeding with his work. Something of the same kind 

 should be done with regard to nature. Eor instance, if any one 

 investigate the vegetation of plants, he should observe from the 

 first sowing of any seed (which can easily be done, by pulling 

 up every day seeds which have been two, three, or four days in 

 the ground, and examining them diligently), how and when the 

 seed begins to swell and break, and be filled, as it were, with 

 spirit ; then how it begins to burst the bark and push out fibres, 

 raising itself a little at the same time, unless the ground be very 

 stiff; then how it pushes out these fibres, some downwards for 

 roots, others upwards for the stem, sometimes also creeping 

 laterally, if it find the earth open and more yielding on one side, 

 and the like. The same should be done in observing the hatch- 

 ing of eggs, where we may easily see the process of animation 

 and organization, and what parts are formed of the yolk, and 

 what 01 the white of the egii, and the like. The same may be 

 said of the inquiry into the formation of animals from putrefac- 

 tion; for it would not be so humane to inquire into perfect and 

 terrestrial animals, by cutting the foetus from the womb ; but 

 opportunities may perhaps be offered of abortions, animals killed 

 in hunting, and the like. Nature, therefore, must, as it were, be 

 watched, as being more easily observed by night than by day : 

 for contemplations of this kind may be considered as carried on 

 by night, from the minuteness and perpetual burning ot our 

 watch-light. 



The same must be attempted with inanimate objects, which 

 ve have ourselves done by inquiring into the opening ot liquids 

 by fire. Por the mode in which water expands is different from 

 that observed in wine, vinegar, or verjuice, and very different, 

 again, from that observed in milk and oil, and the like ; and this 

 was easily seen by boiling them with slow heat, in a glass vessel, 

 through which the whole may be clearly perceived. But we 



all these cases scientific fiicts are elicited, which sense could never li»t« 

 re^ ealed to ua. £d. 



