No. 9. 



Zoology. 



279 



consequent displacement of the water tliat 

 held the lime in the state of hydrate, will 

 rather produce an increase in bulk, than 

 otherwise — the carbonic acid takin;^- the place 

 of the water, a minute crystalization, the 

 result of the re-formation of the carbonate of 

 lime, produces a rirm attachment between 

 • the particles of sand, and also between the 

 mortar and the substance to which it is ap- 

 plied ; the whole necessarily becomes a solid 

 mass. The addition of a greater quantity of 

 lime than what is absolutely necessary to fill 

 the spaces between the particles of sand, 

 would be worse than useless, inasmuch as it 

 would require more than a proportionately 

 longer time to become restored to a state of 

 carbonate, and consequently longer exposed 

 to the inlluence of the atmosphere and water: 

 and when the lime has arrived at a state of 

 carbonate, the hardness and adhesiveness 

 will be lessened in proportion to the increase 

 of the softer material forming the mortar. 



As no change can be effected on the parti- 

 cles of sand, the whole chemical influence 

 will necessarily be exerted on the hydrate 

 of lime. Jly a union of carbonic acid from 

 the atmosphere with the lime, and the con- 

 sequent separation of the water that held the 

 lime in a state of hydrate, a new chemical 

 compound is formed, possessed of different 

 properties : the hydrate, which appears to be 

 destitute of the property of hardening, and 

 retains considerable solubility in water, when 

 changed by a union with carbonic acid, form- 

 ing carbonate of lime, it assumes the proper- 

 ties of induration and insolubility. Hence, 

 mortar cannot be considered as having arrived 

 at its most perfect state of hardness, adhe- 

 siveness and durability, short of a complete 

 decomposition of the hydrate, and the forma- 

 tion of a carbonate has been effected. The 

 time required in producing the change, will 

 be more than proportionate to the quantity — 

 the particles exposed on the surface being 

 first changed to a carbonate, they serve as 

 covering, and protect the deep-seated parti- 

 cles, to a considerable extent, from the influ- 

 ence of the carbonic of the atmosphere: con- 

 sequently, any excess of lime beyond what 

 is necessary to fill the spaces between the 

 particles of sand, will tend to retard the 

 tiardening process ; and when it has arrived 

 at the utmost extent of hardness and adhe- 

 siveness, it will be lessened in proportion to 

 the increase of the lime used. 



The opposition against book-farming, rests 

 on the shoulders of two monsters — ignorance 

 and prejudice. 



All the energy of the hero, and all the 

 science of the philosopher, may find ample 

 BCope in the cultivation of a farm. 



Zoolo$;y« 



Why are certain animals called Mammalia, 

 or Mammifera ! 



Because they have breasts, (inamyncB) with 

 which the females suckle their young. 



Why is the class of mammifera placed at 

 the head of the animal kingdom! 



Because, that not only we ourselves belong 

 to it, but it is that class which possesses the 

 most numerous faculties, tiie most delicate 

 sensations, and the greatest variety of action ; 

 and in which the lissemblage of all these 

 qualities appears so combined as to produce 

 an intelligence more perfect, more fertile in 

 resources, less the slave of instinct, and more 

 capable of progressive perfection, than wiiat 

 is to be found in any of the other classes. 



Why are mammalia and birds called warm 

 blooded 1 



Because their blood is of a heat about one 

 hundred degrees, more or less. 



Why are other animals called viviparous? 



Because they produce their young alive 

 and perfect, (from vious and pario,) as man, 

 quadrupeds, &.c. 



Why are certain animals called verte- 

 brated ! 



Because they have a cranium, or bony 

 cavity, containing the brain, and a succession 

 of bones called the spine, and the divisions 

 of it, verlebrcB, proceeding from the cranium, 

 and containing a prolongation of the brain, 

 denominated spinal marrow. 



Why are other animals called inverte- 

 brated J 



Because they have no vertebrse. 



Why does the faculty of instinct differ from 

 intelligence] 



Because instinct makes animals perform 

 certain actions, necessary to the preservation 

 of the species, but oflen altogether foreign to 

 the apparent wants of the individual; and 

 often, also, extremely complicated. 



We cannot attribute these actions to intel- 

 ligence, without supposing a degree of fore- 

 sight and understanding infinitely superior to 

 what we can admit in the species that per- 

 form them. The actions perfornied by in- 

 stinct are not the eftbrts of imitation, for the 

 individuals that execute them, have often 

 never seen them done by others : they bear 

 no proportion to the common intelligence of 

 the species, but become more singular, more 

 skilful, more distressed, in proportion as the 

 animals belong to the less elevated classes, 

 and are, in other respects, most stupid. Tliey 

 are so much the property of the species, that 

 all the individuals perform them in the same 

 manner, without any improvement 



The working bees have, since the begin- 

 ning of the world, built the most ingenious 

 edifices, agreeably to principles of the high- 



