300 



Lime as a Manure. — Mechanism of the Eye. 



Vol. VI. 



been, inhabited principally by the German 

 race. Its first settlement commenced more 

 than an hundred years ago, yet the gentle- 

 man is still alive who was mainly instru- 

 mental in introducing the use of lime as a 

 manure among them. I had the facts from 

 his own lips. He was an emigrant from 

 Chester county near fifty years ago, where 

 he had witnessed the agricultural value of 

 the article. He found its use practically un- 

 known among the (then) present generation 

 of German farmers, and they received his 

 accounts of its powerful effects in improving 

 soils with the utmost incredulity; and nothing 

 but the actual proof he exhibited to them by 

 his practice could induce them to adopt its 

 use. A considerable portion of the farmers 

 of the upper parts of Montgomery county are 

 of the German race. A gentleman, a native 

 of it, now holding an office in the custom- 

 house of Philadelphia, informed me that when 

 he commenced farming in that district some 

 years ago, lime was but very sparingly used 

 as a manure, and that he was among the first 

 to introduce its systematic use as a part of 

 regular husbandry. 



I have thus thrown loosely together such 

 facts and observations, derived from personal 

 knowledge, or sources on which I can rely, 

 as have led me to the conclusion that the au- 

 thor is incorrect in the assertions quoted in 

 the beginning of this article. I have no wish 

 to detract anything from the well-earned fame 

 of our German farmers, neither am I willing 

 to award them honours to which they are not 

 entitled. I believe the first use of lime as a 

 manure in Pennsylvania, was on the soils 

 covering, and partly derived from, the pri- 

 mary rocks lying south-east of the great lime- 

 stone valley of Chester county, a district in 

 which the Germans were always but a small 

 part of the population. But this is rather a 

 conjecture than anything else, at present. 

 Can any of your readers in that part of the 

 state furnish information on the subject? I 

 am well aware that this is more a matter of 

 curiosity than practical utility, but still its 

 discussion may serve to give variety to the 

 pages of the Cabinet, or fill up a corner when 

 you are hard pushed by the printer for copy. 



S. Lewis. 



Mechanism of the Eye. 

 Birds flying in the air, and meeting with 

 many obstacles, as branches and leaves of 

 trees, require to have |heir eyes sometimes as 

 flat as possible for protection, but sometimes as 

 round as possible, that they may see the small 

 objects, flies and other insects, which they 

 are chasing through the air, and which they 

 pursue with the most unerring certainty ; and 

 this could only be accomplished by giving 

 them a power of suddenly changing the form 



of their eyes. Accordingly, there is a set of 

 hard scales placed on the outer coat of their 

 eye, round the place where the light enters, 

 and over these scales are drawn the muscles 

 or fibres by which motion is communicated ; 

 so that by acting with these muscles the bird 

 can press the scales and squeeze the natural 

 magnifier of the eye into a round shape when 

 it wishes to follow an insect through the air, 

 and can relax the scales in order to flatten 

 the eye again when it would see a distant 

 object, or move safely through leaves and 

 twigs. This power of altering the shape of 

 the eye is possessed by birds of prey in a very 

 remarkable degree. They can thus see the 

 smallest objects close to them, and can yet 

 discern large bodies at vast distances, as a 

 carcass stretched upon the plain, or a dying 

 fish afloat on the water: and a singular provi- 

 sion is made for keeping the surface of the 

 bird's eye clean — for wiping the glass of the 

 instrument as it were — and also for protecting 

 it while rapidly flying through the air with- 

 out hindering the sight. Birds are, for these 

 purposes, furnished with a third eyelid, a fine 

 membrane or skin, which is constantly moved 

 very rapidly over the eyeball by two muscles 

 placed in the back of the eye; one of these 

 muscles ending in a loop, the other in a string 

 which goes through the loop, and is fixed in 

 the corner of the membrane, to pull it back- 

 ward and forward. 



And a third eyelid of the same kind is 

 found in the horse, and is called the haw; it 

 is moistened with a pulpy substance or mu- 

 cilage to take hold of the dust on the eyeball 

 and wipe it clear offj so that the eye is hardly 

 ever seen with anything upon it, though 

 greatly exposed from its size and posture. 

 The swift motion of the haw is given to it by 

 a gristly, clastic substance, placed between 

 the eyeball and socket, and striking obliquely, 

 so as to drive the haw with great velocity 

 over the eye, and then let it come back as 

 quickly. Ignorant persons, when this haw is 

 inflamed from cold, and swells so as to appear 

 — which it never does in a healthy state — 

 often mistake it for an imperfection, and cut 

 it off"; so nearly do ignorance and cruelty pro- 

 duce the same mischief. — Brougham. 



" The man that misses sunrise loses the 

 sweetest part of his existence. I love to watch 

 the first tear that glistens in the opening eye 

 of morning — the silent song the flowers 

 breathe — the thrilling choir of the woodland 

 minstrels — to which the modest brook 

 TRICKLES APPLAUSE — thcsc, swclling out the 

 sweetest chord of sweet creation's matins, 

 seem to pour some soit and merry tale 

 INTO THE daylight's EAR, as if the world 

 had dreamed a happy thing, and now smiled 

 o'er the telling of it !" 



