The Savannah was the first steam vessel to cross the Atlantic Ocean in 1819.

The Savannah

The Savannah was the first steam vessel to cross the Atlantic Ocean in 1819.

The cross section of the Amiens Cathedral. (E) triforium, (F) clerestory.

Amiens Cathedral

The cross section of the Amiens Cathedral. (E) triforium, (F) clerestory.

Monument for Bunker Hill.

Bunker Hill Monument

Monument for Bunker Hill.

The coat of arms of Dominican Republic.

Dominican Republic Coat of Arms

The coat of arms of Dominican Republic.

The Coat of Arms of Greece.

Greek Coat of Arms

The Coat of Arms of Greece.

The Coat of Arms of Italy.

Italian Coat of Arms

The Coat of Arms of Italy.

Jack and Jill falling down the hill.

Jack and Jill

Jack and Jill falling down the hill.

Jack and Jill fallen at the bottom of the hill.

Jack and Jill

Jack and Jill fallen at the bottom of the hill.

In passing through the crystalline, the rays cross each other, so that those rays which pass from the lower part of an object are presented uppermost in the bottom of the eye and the reverse, so that the images of object are always inverted, or bottom side upwards. Labels: a, the aqueous; c, the crystalline; v, the vitreous humor.

Formation of an Image on the Eyeball

In passing through the crystalline, the rays cross each other, so that those rays which pass from the…

The girl taking the goat from the boy in the story Oeyvind and Marit.

Girl with Goat

The girl taking the goat from the boy in the story Oeyvind and Marit.

The cross-section of a beach.

Beach

The cross-section of a beach.

"Idealized section through a dome showing sand-filled channels in cross-section, points of accumulation of oil and gas, and direction of migration." -Johnson, 1916

Oil Accumulation

"Idealized section through a dome showing sand-filled channels in cross-section, points of accumulation…

"Vertical section through a Gulf Coast salt dome." -Johnson, 1916

Salt Dome

"Vertical section through a Gulf Coast salt dome." -Johnson, 1916

"(a)--Diagrammatic cross section of an island or peninsula showing relations of fresh ground water and sea water...(b) Cross section of same island or peninsula showing changes in shape of water table and contact between fresh and salt water resulting from pumping a well." -Gunter, 1933

Water Table

"(a)--Diagrammatic cross section of an island or peninsula showing relations of fresh ground water and…

"Baldwin apple cross pollinated with pollen of the Bellflower apple." -Department of Agriculture, 1899

Baldwin/Bellflower Apple

"Baldwin apple cross pollinated with pollen of the Bellflower apple." -Department of Agriculture, 1899

The cross section view of the steel-track wagon road built on country roads for "cheapness, durability, and reduction of power required to move a vehicle." -Department of Agriculture, 1899

Steel-Track Wagon Road

The cross section view of the steel-track wagon road built on country roads for "cheapness, durability,…

"Two epidermal cells in cross section showing thickened outer wall differentiated into three layers, namely, an outer cuticle, cutinized layer (shaded), and an inner cellulose layer." -Stevens, 1916

Plant Epidermis

"Two epidermal cells in cross section showing thickened outer wall differentiated into three layers,…

"Cross section of a portion of leaf of Ficus elastica showing the multiple epidermis from e to a inclusive; c, cystolith; b, palisade parenchyma; d, spongy parenchyma." -Stevens, 1916

F. Elastica Epidermis

"Cross section of a portion of leaf of Ficus elastica showing the multiple epidermis from e to a inclusive;…

Developmental stages of collenchyma: "1 and 2, cross and longitudinal section of a collenchyma cell in its primary meristem condition." -Stevens, 1916

Collenchyma 1 and 2

Developmental stages of collenchyma: "1 and 2, cross and longitudinal section of a collenchyma cell…

Developmental stages of collenchyma: "3 and 4, longitudinal and cross sections of the same cell at a later stage, the walls in 4 have commenced to thicken at the angles." -Stevens, 1916

Collenchyma 3 and 4

Developmental stages of collenchyma: "3 and 4, longitudinal and cross sections of the same cell at a…

Developmental stages of collenchyma: "5 and 6, longitudinal and cross sections of a mature cell. The arrows indicate the planes through which the longitudinal sections were cut. The stippling inside the walls indicates the protoplasts." -Stevens, 1916

Collenchyma 5 and 6

Developmental stages of collenchyma: "5 and 6, longitudinal and cross sections of a mature cell. The…

Developmental stages of bast fibers: "1 and 2, cross and longitudinal sections of primary meristem cells that are to become bast fibers." -Stevens, 1916

Bast Fibers 1 and 2

Developmental stages of bast fibers: "1 and 2, cross and longitudinal sections of primary meristem cells…

Developmental stages of bast fibers: 3 and 4, cross and longitudinal sections of meristem cells becoming bast fibers.

Bast Fibers 3 and 4

Developmental stages of bast fibers: 3 and 4, cross and longitudinal sections of meristem cells becoming…

"Portion of a cross section of a root of Allium ascalonicum. h, large central, tracheal tube; i, xylem, and l, phloem portion of the vascular bundle; n, cortex cells; 1, endodermis with thin-walled cell at k to admit passage of materials; m, pericycle or pericambium." -Stevens, 1916

A. Ascalonicum Root

"Portion of a cross section of a root of Allium ascalonicum. h, large central, tracheal tube; i, xylem,…

Second developmental stage of sieve tubes, companion cells, and phloem parenchyma. "B, c, companion cells, and d, a beginning sieve tube from c and d, respectively in A. The cross-walls in d are pitted; b, phloem parenchyma grown larger." -Stevens, 1916

Plant Cell Development 2

Second developmental stage of sieve tubes, companion cells, and phloem parenchyma. "B, c, companion…

Third developmental stage of sieve tubes, companion cells, and phloem parenchyma. "The pits in the cross-walls of the sieve tubes become perforations, and the nuclei gone from the cells composing the tube." -Stevens, 1916

Plant Cell Development 3

Third developmental stage of sieve tubes, companion cells, and phloem parenchyma. "The pits in the cross-walls…

"Stages in the development of the elements of the xylem. A, progressive steps in the development of a tracheal tube. 1, row of procambial or cambial cells that are to take part in the formation of a tube; 2, the same at a later stage enlarged in all dimensions; 3, the cells in 2 have grown larger, their cross-walls have been dissolved out, and the wall has become thickened and pitted; 4, the walls in 3 have become more thickened, the pits have an overhanging border, the walls have become lignified as indicated by the stippling, and finally the protoplasts have disappeared, and the tube is mature and dead." -Stevens, 1916

Xylem Development 1

"Stages in the development of the elements of the xylem. A, progressive steps in the development of…

Stages in the development of the elements of the xylem. "B, stages in the formation of tracheids from procambial or cambial cells. The steps are the same as in A, excepting that the cross-walls remain and become pitted." -Stevens, 1916

Xylem Development 2

Stages in the development of the elements of the xylem. "B, stages in the formation of tracheids from…

"Portion of a cross section throughout the stem of Dracaena marginata. P, parenchyma of cortex. V, meristematic zone of the pericycle by the activity of which the stem increases in diameter, with the addition of new vascular bundles. M, mature vascular bundle. N, nearly mature vascular bundle. O, newly formed procambium strand from which a vascular bundle is to arise. B, beginning of a procambium strand by the division of cells in the meristematic zone. F, parenchyma of the fundamental tissue." -Stevens, 1916

D. Marginata Stem

"Portion of a cross section throughout the stem of Dracaena marginata. P, parenchyma of cortex. V, meristematic…

"Diagram showing some types of unusual growth in thickness. A, cross section through a four-year-old stem of Anisostichus capreolata." -Stevens, 1916

A. Capreolata Unusual Stem Growth

"Diagram showing some types of unusual growth in thickness. A, cross section through a four-year-old…

"Diagram showing some types of unusual growth in thickness...B, cross section of stem of species of Bauhinia; the xylem strands, b, are stippled while the surrounding parenchyma and bark tissues are left white." -Stevens, 1916

Bauhinia Unusual Stem Growth

"Diagram showing some types of unusual growth in thickness...B, cross section of stem of species of…

"Diagram showing some types of unusual growth in thickness...C, portion of a cross section of stem of Gnetum scandens; 1, 2, and 3 are successive rings of growth; m, is the pith; b, is a sclerenchyma ring. The xylem portions with the exception of the larger tracheal tubes are shaded, while the medullary rays, phloem and tissues intervening between the rings of growth and the outer cortes tissues are left white." -Stevens, 1916

G. Scandens Unusual Stem Growth

"Diagram showing some types of unusual growth in thickness...C, portion of a cross section of stem of…

"A, cross section through upper half of leaf of Pyrus Japonica, showing cutinized layer of the outer wall at f, and cellulose layer at g." -Stevens, 1916

P. Japonica Epidermis

"A, cross section through upper half of leaf of Pyrus Japonica, showing cutinized layer of the outer…

A cross section through the upper half of a Russian olive leaf, showing a "cutinized layer of the outer wall at f, and cellulose layer at g." -Stevens, 1916

Russian Olive Leaf Epidermis

A cross section through the upper half of a Russian olive leaf, showing a "cutinized layer of the outer…

"C, portion of cross section of submerged stem of Nymphaea odorata, where there is no cutinized layer, and the cuticle is a hardly distinguishable film." -Stevens, 1916

N. Odorata Epidermis

"C, portion of cross section of submerged stem of Nymphaea odorata, where there is no cutinized layer,…

"A, portion of cross section of leaf of Avicennia growing in salty soil; outer wall of epidermis very thick." -Stevens, 1916

Avicennia Epidermis

"A, portion of cross section of leaf of Avicennia growing in salty soil; outer wall of epidermis very…

"B, cross section through skin of apple." -Stevens, 1916

Apple Epidermis

"B, cross section through skin of apple." -Stevens, 1916

"C, cross section through upper half of petal of Japan Quince." -Stevens, 1916

Japan Quince Epidermis

"C, cross section through upper half of petal of Japan Quince." -Stevens, 1916

"Multiple epidermis of leaf of mangrove in cross section. This serves as a water reservoir, and the relatively thick walls of the inner cells reenforce the protective power of the outer layer." -Stevens, 1916

Multiple Epidermis

"Multiple epidermis of leaf of mangrove in cross section. This serves as a water reservoir, and the…

"Cross section of yellow poplar wood. E, early; L, late growth; m, medullary ray." -Stevens, 1916

Yellow Poplar Wood

"Cross section of yellow poplar wood. E, early; L, late growth; m, medullary ray." -Stevens, 1916

"Camera-lucida outline of portion of cross section of cornstalk, showing at g bast fiber zone beneath the epidermis and surrounding the outermost vascular bundles." -Stevens, 1916

Cornstalk Bast Fibers

"Camera-lucida outline of portion of cross section of cornstalk, showing at g bast fiber zone beneath…

"Cross section of a portion of palm stem. e, xylem; f, phloem portions of vascular bundle; g, sclerenchyma tissue about vascular bundle; d, fundamental or ground tissue; c, larger tracheal tubes in vascular bundle." -Stevens, 1916

Palm Stem

"Cross section of a portion of palm stem. e, xylem; f, phloem portions of vascular bundle; g, sclerenchyma…

"Cross section of a root in the region of the root hairs." -Stevens, 1916

Plant Root Hairs

"Cross section of a root in the region of the root hairs." -Stevens, 1916

"Portion of cross section through an aerial root of Stanhopea oculata. h, the velamen; i, exodermis; j, cortex; k, endodermis." -Stevens, 1916

S. Oculata Aerial Root

"Portion of cross section through an aerial root of Stanhopea oculata. h, the velamen; i, exodermis;…

"Cross section through a water-absorbing scale of Tillandsia usneoides; a, a, water-absorbing cells partially filled with water." -Stevens, 1916

T. Usneoides Cell

"Cross section through a water-absorbing scale of Tillandsia usneoides; a, a, water-absorbing cells…

"B, diagram of vascular bundles in external view and in cross section of the stem of Cerastium. The leaves are shown cut off at 1, 2, 2' and 3." -Stevens, 1916

Cerastium Stem

"B, diagram of vascular bundles in external view and in cross section of the stem of Cerastium. The…

"Semi-diagrammatic cross section of a leaf showing by arrows how the water passes from the tracheal elements of a vein into the border parenchyma cells, and thence into the palisade and spongy parenchyma, from which it evaporates into the intercellular spaces and passes from the leaf through the stomata. a, upper epidermis; b, lower epidermis; c, palisade parenchyma; g, spongy parenchyma; d, border parenchyma; e, tracheal elements; and the stippled cells bellow e, the phloem cells." -Stevens, 1916

Leaf Water Flow

"Semi-diagrammatic cross section of a leaf showing by arrows how the water passes from the tracheal…

The cross section of the stem of hop, which carries large amounts of water.

Hop Stem Tissue

The cross section of the stem of hop, which carries large amounts of water.

The cross section of the stem of yellow poplar, which carries large amounts of water.

Yellow Poplar Stem Tissue

The cross section of the stem of yellow poplar, which carries large amounts of water.

The cross section of the stem of water cress, which carries very little water.

Water Cress Stem Tissue

The cross section of the stem of water cress, which carries very little water.

The cross section of the stem of Pisdium Galapageium, which carries very little water.

P. Galapageium Stem Tissue

The cross section of the stem of Pisdium Galapageium, which carries very little water.

"A typical stoma in cross section and surface view combined. k, guard cell; j, the gap or stoma between the guard cells; l, epidermal cell bordering a guard cell." -Stevens, 1916

Stoma

"A typical stoma in cross section and surface view combined. k, guard cell; j, the gap or stoma between…

"A, diagram showing relative position of the guard cells in cross section in the open and closed positions; the heavier line indicates the open position." -Stevens, 1916

Stoma Guard Cells

"A, diagram showing relative position of the guard cells in cross section in the open and closed positions;…

"A, cross section of stem of Juncus...the black lines traversing the section are really chains of cells and thin-walled cells with relatively large intercellular spaces between them fill up i." -Stevens, 1916

Juncus Stem

"A, cross section of stem of Juncus...the black lines traversing the section are really chains of cells…

"Cross section of a portion of the blade of a leaf, showing upper epidermis at a, lower epidermis at b, palisade parenchyma at c, spongy parenchyma at d, and tracheids from the end of a vein at e." -Stevens, 1916

Leaf Epidermis

"Cross section of a portion of the blade of a leaf, showing upper epidermis at a, lower epidermis at…

"Cross section through a portion of rubber leaf, showing the large percentage of water-storage tissues on both sides of the leaf, and the relation of the palisade and spongy parenchyma to the lateral veins." -Stevens, 1916

Rubber Leaf Cells

"Cross section through a portion of rubber leaf, showing the large percentage of water-storage tissues…

"Cross section of a portion of a leaf of Indian corn. a, upper and b, lower epidermis; c, c, palisade cells; n, border parenchyma containing starch within its chloroplasts; e, vascular bundle; d, d, stomata." -Stevens, 1916

Indian Corn Leaf Cells

"Cross section of a portion of a leaf of Indian corn. a, upper and b, lower epidermis; c, c, palisade…

"Cross section of a portion of leaf of Codonanthe, showing the water-storage tissue at f, and the chlorophyll-bearing tissues at e." -Stevens, 1916

Codonanthe Leaf Tissues

"Cross section of a portion of leaf of Codonanthe, showing the water-storage tissue at f, and the chlorophyll-bearing…

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below." -Stevens, 1916

Spirogyra Chloroplast

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below."…

"Cross section through the thallus of Marchantia. j, stoma leading into a relatively large air-chamber in which arise numerous cells with chloroplasts, k; l, l, cells forming partitions between the air-chambers; m, cells destitute of chloroplasts and with numerous oblong pits; h, upper, and i, lower epidermis." -Stevens, 1916

Marchantia Thallus

"Cross section through the thallus of Marchantia. j, stoma leading into a relatively large air-chamber…