An illustration of a young cow eating hay out of a trough and a dog peeking around the corner.

Cow Eating Hay in Barn

An illustration of a young cow eating hay out of a trough and a dog peeking around the corner.

An illustration of a trough fault.

Trough Fault

An illustration of a trough fault.

An overthrust anticline of a strata fold.

Overthrust Anticline Folds

An overthrust anticline of a strata fold.

An overthrust anticline of a strata fold.

Overthrust Anticline Folds

An overthrust anticline of a strata fold.

"A syncline is a downfolding of the strata in the form of a trough, as at a...An anticline is an upfolding of the strata in the form of an arch, as at b." -Dryer, 1901

Strata Folds

"A syncline is a downfolding of the strata in the form of a trough, as at a...An anticline is an upfolding…

"A form of dough-making machine in common use. It consists of a trough or box, the lower portion of which is semi-cylindrical, hung on a spindle, with a series of iron crossbars revolving inside. It is made to be worked by either hand or steam-power, and of various sizes, as required by bakers. In this machine the whole of the operations connected with setting the sponge, breaking the sponge, and mixing the dough, are performed. The gearing is arranged to give a fast motion for setting the sponge, and a slow motion towards the close of the dough making, when it is desireable to draw out the mass in order to give it a "skin," or smooth superficial texture." — Encyclopedia Britanica, 1893

Kneading Machine

"A form of dough-making machine in common use. It consists of a trough or box, the lower portion of…

"A kneading-machine of a highly approved form, used in the great Scipion bakery of Paris, the invention of M. Boland. Externally it is like the former, and it is also geared to move at two rates of rapidity. It has further an adjustment by which the force of the motion is increased while its rate is diminished." — Encyclopedia Britanica, 1893

Kneading Machine

"A kneading-machine of a highly approved form, used in the great Scipion bakery of Paris, the invention…

"The trough is a castiron basin, which turns on a vertical axis. The interior is provided with a kneader, shaped like a lyre, which first works up the dough and then divides it during the entire period of operation. Two other implements are also used, of a helical form, to draw out and inflate the dough in all directions, part by part, as is practised in kneading by hand." — Encyclopedia Britanica, 1893

Kneading Machine

"The trough is a castiron basin, which turns on a vertical axis. The interior is provided with a kneader,…

Two boys pumping water into a trough.

Boys Pumping Water

Two boys pumping water into a trough.

"This machine consists of two vertical shafts, carrying radial arms. These arms pass each other in opposite directions, so that, in addition to a tearing action on the dough, which the knives have on passing each other, they have a screw action, pressing the dough down on one side and up on the other. The vessels containing the dough are made of wood, of an oval form, to correspong with the action of the machine." — Encyclopedia Britanica, 1893

Vertical Mixer

"This machine consists of two vertical shafts, carrying radial arms. These arms pass each other in opposite…

"Start a trough from A. At the moment of its reflection as a crest a B, start a crest at A as shown. The two crests will meet near the middle of the rope. The crest at the point and moment of meeting results from two forces acting in the same direction; their resultatnt is greater than either of the components." -Avery 1895

Constructive Interference

"Start a trough from A. At the moment of its reflection as a crest a B, start a crest at A as shown.…

"Using the rope...start a crest at A. At the moment of its reflection at B as a trough, start a second crest at A. The trough and crest will meet near the middle of the rope. the rope particles at this point, being thus simultaneously acted upon by opposite forces, will remain at rest or nearly so." -Avery 1895

Destructive Interference

"Using the rope...start a crest at A. At the moment of its reflection at B as a trough, start a second…

"Suport a soft cotton rope several yards long between two fixed supports, as the opposite sides of the room, or the floor and the ceiling. With a ruler, strike the rope a blow near one end so as to form a crest, as shown. Vary the tension of the rope if necessary, until the crest is easily seem. Notice the crest, c, travels from A to B, where it is reflected back to A as a trough, t." -Avery 1895

Fixed Wave Reflection

"Suport a soft cotton rope several yards long between two fixed supports, as the opposite sides of the…

"Tie one end of a soft cotton rope about 20 feet long to a fixed support, and hold the other end in the hand. Move the hand up and down with a quick, sudden motion, so as to set up a series of waves in the rope, as shown, in which each curved line may be considered an instantaneous photograph of a rope thus shaken." -Avery 1895

Form of Waves

"Tie one end of a soft cotton rope about 20 feet long to a fixed support, and hold the other end in…