CELLS NOT LIKE BRICKS IN A WALL. 73 



— All that is essential in the cell or elementary part 

 is matter that is in the living state, germinal matter, 

 and matter that ^cas in the living state, formed 

 material. With these is usually associated a certain 

 proportion of* matter about to become living, the pabu- 

 lum or food. So that we may say that in every living 

 thing we have matter in three different states : — 



Matter about to become living ; 



Matter actually living ; and 



Matter that has lived. 



The last, like the first, is non-living, but, unlike 

 this, it has been in the living state, and has had im- 

 pressed upon it certain characters which it could 

 not have acquired in any other way. By these cha- 

 racters we know that it lived, for we can no more 

 cause matter artificially to exhibit tlie characters of 

 the dried leaf, the lifeless wood, shell, bone, hair, or 

 other tissue, than we can make living matter itself, 

 in our laboratories. 



111. Cells not like bricks in a wall. — Cells forming 

 a tissue have been compared to bricks in a wall, but 

 the cells are not like bricks, having the same con- 

 stitution ia every part, nor are they made first and 

 then embedded in the mortar. Each brick of- the 

 natural wall grows of itself, places itself in position, 

 forms and embeds itself in the mortar of its own 

 making. The whole wall grows in every part, and, 

 while growing, may throw out bastions which grow 

 and adapt themselves perfectly to the altering struc- 

 ture. Even now it is argued by some that, because 

 things, like fully formed cells, may be made arti- 

 ficially, the actual cells are formed in the same sort 

 of way — an argument as cogent as would be that of 

 a person who, after a visit to Madame Tussaud's 

 exhibition, seriously maintained that the textures of 

 our bodies were constructed upon the same principles 

 as the life-like wax fio-ures. 



lia. Cells contain no molecular machinery. — Every 



