96 SELECTED ESS A YS FROM LA Y SERMONS 



portion of protoplasm may successfully take on the function 

 of feeding, moving, or reproducing apparatus. In the high- 

 est, on the contrary, a great number of parts combine to 

 perform each function, each part doing its allotted share of 

 the work with great accuracy and efficiency, but being use- 

 less for any other purpose. 



On the other hand, notwithstanding all the fundamental 

 resemblances which exist between the powers of the proto- 

 plasm in plants and in animals, they present a striking 

 difference (to which I shall advert more at length presently), 

 in the fact that plants can manufacture fresh protoplasm 

 out of mineral compounds, whereas animals are obliged to 

 procure it ready made, and hence, in the long run, depend 

 upon plants. Upon what condition this difference in the 

 powers of the two great divisions of the world of life depends, 

 nothing is at present known. 



With such qualifications as arises out of the last-mentioned 

 fact, it may be truly said that the acts of all living things are 

 fundamentally one. Is any such unity predicable of their 

 forms? Let us seek in easily verified facts for a reply to 

 this question. If a drop of blood be drawn by pricking one's 

 finger, and viewed with proper precautions, and under a 

 sufficiently high microscopic power, there will be seen, 

 among the innumerable multitude of little, circular, dis- 

 coidal bodies, or corpuscles, which float in it and give it its 

 colour, a comparatively small number of colourless corpus- 

 cles, of somewhat larger size and very irregular shape. If 

 the drop of blood be kept at the temperature of the body, 

 these colourless corpuscles wdll be seen to exhibit a marvel- 

 lous activity, changing their forms with great rapidity, draw- 

 ing in and thrusting out prolongations of their substance, 

 and creeping about as if they were independent organisms. 



The substance which is thus active is a mass of proto- 



