This figure, representing Acanthite, an orthrohombic  crystal, shows a combination of the following forms: (a), (b), (c), (l), (m), (o), (e), (d), (k), (p), (s), (r), and (n).

Acanthite

This figure, representing Acanthite, an orthrohombic crystal, shows a combination of the following forms:…

Iron Sulpharsenide (Arsenopyrite), bounded by ∞P, {110} (M), and 1/3P∞̆, {013} (r), forms penetration twins of two individuals, where P∞̄, {101} acts as twinning plane.

Arsenopyrite

Iron Sulpharsenide (Arsenopyrite), bounded by ∞P, {110} (M), and 1/3P∞̆, {013} (r), forms penetration…

This figure shows the combination of forms on calcium hyposulphite (CaS_2_O_3_ + 6 aq). If we assume the face c as the basal pinacoid, and b as the brachypinacoid, then the symbols of the other planes become: (p), (p'), and (q).

Calcium Hyposulphite

This figure shows the combination of forms on calcium hyposulphite (CaS_2_O_3_ + 6 aq). If we assume…

The Copper Sulphide, Chalcocite, forms three kinds of twins symmetrical to ∞P, {110}, to 4/3P∞̆, {043}, and to 1/2P, {112} respectively. The latter is shown in this figure.

Chalcocite

The Copper Sulphide, Chalcocite, forms three kinds of twins symmetrical to ∞P, {110}, to 4/3P∞̆,…

This figure represents a crystal of iron pyrite showing representatives of all the forms of the isometric system except the rhombic dodecahedron: ∞O∞ {100} (P); O, {111} (d); [∞O2/2], π{102} (e); [4O2/2], π{214} (s); 2O2, {211} (o); and 3O, {133} (t). It is shortened in the direction of one of the principal axes, which, together with the fact that only two of the three faces belonging to the forms s, o, and t are developed in each octant, gives to it a decidedly orthorhombic habit.

Crystal of Iron Pyrite Showing Representatives of All the Forms of the Isometric System

This figure represents a crystal of iron pyrite showing representatives of all the forms of the isometric…

Cubes of Iron Pyrites frequently show a striation of their planes in one direction, which is perpendicular to the striation  on all contiguous faces, owing to oscillatory combination with the pentagonal dodecahedron. This would not be possible in a holohedral cube.

Cube of Iron Pyrite

Cubes of Iron Pyrites frequently show a striation of their planes in one direction, which is perpendicular…

This illustration shows the first stage in the manufacturing of glue. The material used for making the glue (either animal bone or hide) is soaked in a milk of lime (or in some cases, Hydrochloric or Sulfurous acid) to purify and loosen particles.

First Stage in Glue Manufacturing

This illustration shows the first stage in the manufacturing of glue. The material used for making the…

This figure reproduces a crystal of Hydrous Copper Sulphate whose forms are (c), (a), (b), (n), (m), (l), and (s).

Hydrous Copper Sulphate

This figure reproduces a crystal of Hydrous Copper Sulphate whose forms are (c), (a), (b), (n), (m),…

Orthorhombic Iron Disulphide (Marcasite) sometimes shows cyclic groups of five individuals, bounded by ∞ P, {110} (M); P∞̆, {011} (l); and 0P, {001}, and united into a pentagonal figure by (M) as twinning plane.

Marcasite

Orthorhombic Iron Disulphide (Marcasite) sometimes shows cyclic groups of five individuals, bounded…

It has been observed that the pentagonal dodecahedron, [∞o2/2], π {201}, on pyrite may have but six of its twelve planes developed in such a manner a to produce an apparent rhombohedron.

Pyrite

It has been observed that the pentagonal dodecahedron, [∞o2/2], π {201}, on pyrite may have but six…

"The sulphur is then further purified by heating it in iron vessels (retorts) without access of air, until it is vaporized. the vapor is led into brick-lined rooms. A part of the gas is suddenly cooled and is deposited as a fine powder on the sides of the room. The form is known as flowers of sulphur. Most of the sulphur vapor condenses in the liquid form, and flows down to the outlet of the condensing chamber." -Brownlee 1907

Sulfur Purification

"The sulphur is then further purified by heating it in iron vessels (retorts) without access of air,…

This figure shows an orthorhombic crystal of sulphur, showing the forms: (p), (s), (c), and (n).

Sulphur

This figure shows an orthorhombic crystal of sulphur, showing the forms: (p), (s), (c), and (n).

Laboratory preparation of sulphur trioxide, an important step in the process of making sulphuric acid. "Sulphur (a) burns in the air drawn into the apparatus by an aspirator, and thte sulphur dioxide formed passes with the excess of air into the U-tube (b) which is filled with some loose material to rid the gases of sulphur dust. In the bottle (c) the gases lose their moisture as they make their way through the flass beads drenched with concentrated sulphuric acid. The patinized asbestos in the tube (d) is gently heated, and brings about the union of the sulphur dioxide with the oxygen of the air. The sulphur trioxide resulting from the action is absorbed by concentrated sulphuric acid trickling down through the apparatus (e)." -Brownlee 1907

Sulphur Trioxide Preparation

Laboratory preparation of sulphur trioxide, an important step in the process of making sulphuric acid.…

Diagrammatic representation of the sulphuric acid contact process. "Sulphur, or ores containing sulphur, are burned in air. The sulphur dioxide and the other gaseous products of the combustion are cooled, freed from dust, arsenic, and most of the moisture, then mixedwith air and passed through a tube containing a catalytic agent, usually finely divided platinum. The oxygen of the air cmbines with the sulphur dioxide and forms the trioxide, which is then combined with water to form sulphuric acid." -Brownlee 1907

Sulphuric Acid Contract Process

Diagrammatic representation of the sulphuric acid contact process. "Sulphur, or ores containing sulphur,…