=450 Italian.= 451 Orthography. 452 Etymology. 453 Dictionaries. 454 Synonyms. 455 Grammar. 456 Prosody. 457 Dialects. 458 Texts. 459 Romansh and Wallachian.

=460 Spanish.= 461 Orthography. 462 Etymology. 463 Dictionaries. 464 Synonyms. 465 Grammar. 466 Prosody. 467 Dialects. 468 Texts. 469 Portuguese.

=470 Latin.= 471 Orthography. 472 Etymology. 473 Dictionaries. 474 Synonyms. 475 Grammar. 476 Prosody. 477 Dialects. 478 Texts. 479 Medieval Latin.

=480 Greek.= 481 Orthography. 482 Etymology. 483 Dictionaries. 484 Synonyms. 485 Grammar. 486 Prosody. 487 Dialects. 488 Texts. 489 Modern Greek.

=490 Other Languages.= 491 Chinese. 492 Egyptian. 493 Semitic. 494 Indian. 495 Iranian. 496 Keltic. 497 Slavic. 498 Scandinavian. 499 Other.

NATURAL SCIENCE.

=500 Natural Science.= 501 Philosophy. 502 Compends. 503 Dictionaries. 504 Essays. 505 Periodicals. 506 Societies. 507 Education. 508 Travels. 509 History.

=5l0 Mathematics.= 511 Arithmetic. 512 Algebra. 513 Geometry. 514 Trigonometry. 515 Conic sections. 516 Analytical geometry. 517 Calculus. 518 Quaternions. 519 Probabilities.

=520 Astronomy.= 521 Theoretical. 522 Practical. 523 Descriptive. 524 Maps. 525 Observations. 526 Figure of the earth. 527 Navigation. 528 Almanacs. 529 Chronology.

=530 Physics.= 531 Mechanics. 532 Hydrostatics. 533 Pneumatics. 534 Acoustics. 535 Optics. 536 Heat. 537 Electricity. 538 Magnetism. 539 Molecular physics.

=540 Chemistry.= 541 Theoretical. 542 Experimental. 543 Analysis. 544 Qualitative. 545 Quantitative. 546 Inorganic. 547 Organic. 548 Crystallography. 549 Mineralogy.

=550 Geology.= 551 Physical Geography, Meteorology. 552 Lithology. 553 Dynamical geology. 554 Europe. 555 Asia. 556 Africa. 557 North America. 558 South America. 559 Oceanica.

=560 Paleontology.= 561 Plants. 562 Invertebrates. 563 Protozoa and Radiates. 564 Mollusca. 565 Articulates. 566 Vertebrates. 567 Fishes. 568 Reptiles and Birds. 569 Mammals.

=570 Biology.= 571 Prehistoric Archaeology. 572 Ethnology. 573 Natural History of Man. 574 Homologies. 575 Evolution. 576 Embryology. 577 Spontaneous generation. 578 Microscopy. 579 Collectors’ Manuals.

=580 Botany.= 581 Physiological. 582 Systematic. 583 Ornamental. 584 Europe. 585 Asia. 586 Africa. 587 North America. 588 South America. 589 Oceanica.

=590 Zoology.= 591 Comparative Anatomy. 592 Invertebrates. 593 Protozoa and Radiates. 594 Mollusca. 595 Articulates. 596 Vertebrates. 597 Fishes. 598 Reptiles and Birds. 599 Mammals.

USEFUL ARTS.