22 BORDER LINES OF KNOWLEDGE 



sues down to the bone on wliich they lie, as if the skin 

 were transparent as the cornea, and the organs it cov- 

 ers translucent as the gelatinous pulp of a medusa. 



It is curious that the Japanese should have antici- 

 pated Europe in a kind of rude regional anatomy. I 

 have seen a manikin of Japanese make traced all over 

 with lines, and points marking their intersection. By 

 this their doctors are guided in the performance of acu- 

 puncture, marking the safe places to thrust in needles, 

 as we buoy out our ship-channels, and doubtless indi-' 

 eating to learned eyes the spots where incautious med- 

 dling had led to those little accidents of shipwreck to 

 which patients are unfortmiately liable. 



A change of method, then, has given us General 

 and Regional Anatomy. These, too, have been 

 worked so thoroughly, that, if not exhausted, they 

 have at least become to a great extent fixed and pos- 

 itive branches of knowledge. But the first of them, 

 General Anatomy, would never have reached tliis 

 positive condition but for the mtroduction of that in- 

 strument which I have mentioned as the second great 

 aid to modern progress. 



This instrument is the achromatic microscope. For 

 the history of the successive steps by which it became 

 the effective scientific implement we now possess, I 

 must refer you to the work of Mr. Quekett, to an 

 excellent article in the Penny Cyclopaedia, or to that 

 of Sir David Brewster in the Encyclopaedia Britannica. 

 It is a most interesting piece of scientific history, which 



