63 



NUTCRACKER. 



NUTTALITE. 



mine of Nussiere, near Beaujeu, department of tha Rhone, France 

 The following is the analysis by Barruel : 



Phosphate of Lead 

 Phosphate of Lime 

 Chloride of Lead 

 Arseniate of Iron . 



56-40 



22-20 



7-65 



6-50 



-9275 



NUTCRACKER. [NuciFBAOA.] 



NUTHATCH. [SITTA.] 



NUTMEG. [MYRISTICA.] 



NUTRITION. One of the chief differences between iuorganie and 

 organic bodies is, that the former retain their form and other charac- 

 ters by a passive resistance to change ; the latter by a constant change 

 of tbeir particles, in which those that in the constant actions of life 

 or by the influence of external agents have been destroyed, are replaced 

 by others similar to themselves. This constant change is effected by 

 the process of nutrition. Nutrition is the last step of the general 

 process of assimilation, by which living bodies convert the materials 

 which they derive from their food into substances like their own, and 

 appropriate the materials thus changed to their own increase or repair. 

 The several nutritive matters received into the living body are variously 

 altered by digestion, absorption, respiration, and by all the other 

 changes which the blood or other fluid undergoes in ita passage to the 

 several parts of the frame ; these changes constitute the process of 

 assimilation, at the end ef which each part of the body abstracts from 

 the general and homogeneous mass of nutritive fluid that which is 

 required for its own growth or repair ; muscle abstracting particles to 

 form muscle, nerves from the same fluid abstracting particles to form 

 nerve, and so on. 



That a constant change of particles goes on in the majority of the 

 tissues of the living body may be considered certain. It is evidently 

 necessary from the nature of the case ; for the living body is exposed 

 to the game external agents as inorganic matter is, and all its own 

 actions are so many more sources of waste to each tissue. Some 

 constant power of repair must therefore be requisite to maintain 

 living bodies in a state of integrity against these constant sources of 

 waste ; and that power is exerted in nutrition. Its influence is shown 

 in the fact that the living body retains throughout life, or a great 

 portion of it, its form and composition less altered than the most solid 

 of inorganic matters exposed to similar influences. Within certain 

 limits also, the greater the waste the greater the nutritive supply : thus, 

 for example, by constant exercise the size of the muscles, so far from 

 being decreased, is ultimately increased, the effect of nutrition being 

 not only to replace that which was destroyed, but to supply a certain 

 quantity more. We may clearly observe an application of the same 

 law in the cuticle ; that in the palm of the hand is more than twice 

 as thick as that on the back of the arm, yet the former is subject to 

 the most friction ; and if the friction of the palm be greatly increased, 

 the cuticle, notwithstanding the igreater waste, increases in thickness 

 in a yet greater proportion, so ss to defend the subjacent skin from the 

 greater source of injury to which it is exposed. 



It is true that when the body does not change in any of its sensible 

 qualities, we cannot be so well assured of any change of particles still 

 going on ; but we may reasonably assume that the two parts of nutri- 

 tion, the removal of old and addition of new particles, which at other 

 times we trace producing either an increase or decrease of the body, as 

 one or the other of them predominates, are exactly balanced. If we 

 examine, for example, the growth of any hollow organ of the body, as 

 the heart, we find that in advancing years from childhood to manhood, 

 it increases not only in its whole bulk, but aLo in the size of its cavities, 

 and that, at every period of life, the size of the cavities and the thick- 

 ness of their walls bear nearly the same proportion. Now, if only an 

 addition were made to the exterior of the heart of a child, its whole 

 bulk would be increased, but the size of its cavities would be dispro- 

 portionately small. We must therefore assume that substance is 

 removed from the interior of the heart, at the same time, though not 

 in exactly the same quantity, that substance is added to its exterior. 

 In like manner, when the heart diminishes in size, as it usually does 

 in persons labouring under consumption, material must be at the same 

 time abstracted from the exterior, and, in rather a leas proportion, 

 added to the interior. Whatever of this kind is true of the larger 

 organs must be equally so of the small ones ; so long as they preserve 

 the tame form and proportions, no change of size can take place without 

 the concurrence of the two processes of nutritive deposition and 

 absorption ; when the former preponderates, the part will increase in 

 size when the latter preponderates, it will diminish; the former, 

 when connected with disease is named Hypertrophy [HYPERTROPHY, 

 in Aura ANI> Sc. Div.], the latter Atrophy. [ATROPHY, in ARTS AKD 

 8c. Div. | 



The coincidence of these two processes, where any change of size 

 takes place, being thai proved, and their continuance, when no such 

 : change occurs, being necessary, we may fairly assume that in 

 the latter cace, in the state of nutritive equilibrium, they still con- 

 tinue, though their opposite effects being exactly balanced, the 

 ultimate result is not discernible. Popular belief, adopting this idea 

 as on* of whoee truth there could be no possible doubt, has even 

 assigned the periods of time in which one whole set of particles is 



removed and replaced. There is no evidence whatever upon which 

 any such calculation can be made ; the period in which an entire 

 change is completed probably varies greatly in different tissues aud 

 different external circumstances, and in the bones and teeth it is pro- 

 bable that the particles once deposited are never removed, so long as 

 the animal's size and other characters remain unaltered. 



The process of nutrition is concerned in the production of two 

 apparently different results that of development and that of growth. 

 In development the added particles not merely increase the size of 

 the part, but produce a change in its form or its substance. Thus, the 

 whole body, with all its varieties of tissues, and through all its 

 changes of form, is developed by nutrition, from a small part of a 

 little sac [REPRODUCTION], which, to all appearance, is composed of 

 homogeneous materials. In growth each part increases by the pre- 

 dominant deposition of particles with'iu and around those of which it 

 was previously composed, and similar to them. These two nutritive 

 processes, though in the period of life previous to the adult age they 

 are usually concurrent, may go on independently of each other. Thus 

 the body may be deficient in development, some part of it being 

 monstrous, that is, remaining of the same form as that which it had 

 in the embryonic state [MONSTER], and yet with this defect in form it 

 may increase in size, for monsters are commonly well grown ; and, on 

 the other hand, being perfect in development and form, the body, or 

 some part of it, may be deficient in size. A dwarf is an example of 

 a defect of growth ; a hare-lip, a cleft palate, an anormal uuossified 

 cartilage, are examples of defects of development : both are defects 

 in the process of nutrition, but the failure is in each in a different 

 direction. 



One of the most important facts in regard to the process of nutrition, 

 in both plants aud animals, is that all tissues originate in cells. [CELL.] 

 It is by the activity of these cells that all the processes of nutrition 

 are carried on. In plants, they appropriate the inorganic or mineral 

 matters and convert them into organic. In animals, they absorb the 

 nutrient materials supplied by the chemistry of the plant-cell, and aro 

 the great agents by which these materials are first made subservient 

 to life, and afterwards thrown off from the body. [ANIMAL KINGDOM ; 

 VEGETABLE KINGDOM.] In plants the materials of nutrition are 

 brought to the cells by means of the sap, whicli consists of water 

 holding other materials in solution. [SAP.] In the higher animals 

 the blood is the great source of the materials from which the cells 

 derive their constituents. [BLOOD.] 



Thus the process of organic nutrition is widely different from that 

 by which inorganic masses increase in size, as in crystallisation, which, 

 as in it alone inorganic matter acquires definite forms as it increases, 

 can alone be compared with organic growth. In crystallisation tho 

 addition of similar particles is entirely by external apposition, and tho 

 crystal has no power of attracting the particles of any matter different 

 from its own. Organic particles (as cells), on tho contrary, not only 

 attract particles into their interior spaces, but alter them on their 

 passage, decomposing them from their previous elementary compo- 

 sition, and recombining them into matter like their own. 



In healthy nutrition each part appropriates particles similar to its 

 own, or differing according to certain laws of development; in disease, 

 parts frequently appropriate other substances than their own, and all 

 the solid products of various diseases may be regarded as the effects 

 of morbid processes of nutrition. Some of these are formed according 

 to the laws of normal development, and are only morbid because out 

 of place, as cicatrices, adhesions, and the other similar products of 

 simple inflammation ; others are produced by the deposition of sub- 

 stances different from any of those already existing in the body, as in 

 the production of various tumours. The former are composed of a 

 tissue similar to cellular tissue, but the injuries of parts are but 

 partially repaired by it, because the new tissue, which is in all cases 

 nearly the same, differs in many of its characters from that which it 

 replaces. 



The most complete exercise of the process of nutrition in repairing 

 injuries, whether from accident or disease, is exhibited in the regeneration 

 of parts, but in man and the higher animals there nre but few examples 

 of a perfect reproduction of the injured or destroyed tissue. The 

 Dones and the non-vascular tissues are probably the only instances in 

 which a tissue destroyed by disease or internal injury is replaced by 

 one similar to itself. 



In all these cases of repair or regeneration of tissue, the same 

 process of the effusion of nutritive matter and the several stages of 

 "ortnation and alteration of the cells is gone through which is observed 

 n the first development of the tissues. But the process fails before 

 the higher changes are accomplished, aud the repairing tissue acquires 

 only a low degree of development. As far also as they have been at 

 present examined, the various morbid growths appear to be formed on 

 a similar plan, and to proceed from a formation of primary cells. 



NUTTAINIA, a genus of Trilobila, from the Silurian Strata of 

 Tyrone. (Portlock.) It occurs also in England and Wales. 



NUTTALITE, a Mineral which occurs crystallised. Primary form 

 a square prism. Cleavage parallel to the lateral planes. Fracture 

 uneven. Hardness 4-0 to 4-5. Colour gray. Lustre vitreous. Trans- 

 ucent. Specific gravity 27 to 2'8. It is found at Bolton in Mav 

 sachusetts imbedded in calcareous spar. An analysis by Thomson 

 gives : 



