6 



t>OPIJLAtl SCIENCE NE#S. 



[Januah-^ , iSSfj. 



SULPHUR. 



SuLPHUii is an element of great interest, both 

 chemically and practically. Its most impor- 

 tant commercial use is in the manufacture of 

 sulphuric acid, as described in the June 

 number. It also presents many chemical 

 peculiarities wortliv of consideration. 



Sulphur is one of the few elements which 

 occur abundantly in the free state uncombined 

 with other substances. Carbon is the only- 

 element which surpasses it in tiiis respect, 

 excepting, of course, the free oxygen and nitro- 

 gen of the air. It is also foimd combined with 

 nearly all the metals forming sidphides. The 

 only sulphin-niines of importance are in the 

 volcanic districts of Sicil}-. These mines have 

 l)een worked for over three hinidred years ; 

 but since sulphuric acid has been made from 

 pyrites, they have become of less importance, 

 and the amount of sulphur produced is de- 

 creasing. 



The numerous allotropic forms which sul- 

 phur takes is one of its most striking peculiar- 

 ities. As it occurs in nature, it is a pale- 

 yellow resinous solid, crvstallizing in trimetric 

 octahedrons ; but when melted, and allowed to 

 crystallize by cooling, monoclinic prisms are 

 formed, which, after a short time, without 

 changing their shape, are transformed into a 

 mass of minute octahedra of the first variety. 

 Ifeth crvstalline forms mav be obtained at the 

 same temperature from a super-saturated solu- 

 tion of sulphur in benzol bv dropping in a 

 crystal of the form required. The trimetric 

 sidphiu" fuses at 239'' F., and has the specific 

 gravity 2.05 ; while the triclinic crystals have 

 a specific gravity 1.9S, and fuse at 248'''. 



When sulphur is heated, a very interesting 

 series of phenomena result. At 239*^ F. it 

 melts to a limped pale-yellow liquid ; but if 

 the heating be continued, it becomes thicker 

 and darker-colored, imtil at 356° it is nearly 

 black and opaque, and thick as tar. Con- 

 tinuing the heating to 500'', it becomes quite 

 liquid again. If in this condition the sulphur 

 is poured into cold water, it will, upon cooling, 

 form a soft, elastic, rubber-like mass, which, 

 however, in a few hours spontaneously changes 

 into the ordinary trimetric crystalline \ariety. 



At 836° sidphin- boils, giving oft" a browni.sh- 

 red vapor. When this is condensed it forms 

 the fine powder known as flowers of sulphur, 

 whinh appears to be made up of two modifi- 

 cations of the element, one of which, like the 

 common brimstone, is soluble in l)isulphide 

 of carbon, while the other is insoluble. These 

 two forms appear to be distinct varieties of 

 the element, correspcmding to the two classes 

 of basic and acid compounds which it forms. 

 A black and red variety ha^■e also been de- 

 scribed. 



We thus have at least four, and perhaps 

 more, distinct varities of this single element, 

 ull of which are sulphur, and nothing else, 

 • — the trimetric and monoclinic crystals, the 



amorphous, ductile form, and the insoluble 

 modification. It is hard to explain the exist 

 ence of these varieties on the theor\ that 

 sulphur is a simple elementary substance, but 

 there is no evidence whatever to the contrary. 

 No known reagents can split the element up 

 into two or more substances : and for tiie pros 

 ent we must beliexe that it is but one sub- 

 stance, and refer its difterent changes o 

 physical form to tlie arrangement of the chem- 

 ical atoms, out of xyhicii the physical molecule 

 is built up. Certain results obtained from 

 determinations of the specific gravity of its 

 vapor at diflerenttemperaturestend to confirm 

 this view, and show an increasing simplicity 

 of molecular constitution as the temperature 

 increases ; but the actual and true reason for 

 these protean changes in physical appearance 

 is still unknown to us. 



Sulphur is closely allied chemically to oxy- 

 gen. It unites with metals in the same way. 

 forming sulphides. Many elements will bmn 

 in sulphm- \apor as in oxygen, uniting with 

 it directly ; and there is a well-marked class 

 of sidphiu' acids in which the oxygen is re- 

 placed by sulphur, which imite in the same 

 way with bases, forming an important class 

 of salts which includes many \aluable miner- 

 als. For a single example, we may mention 

 the sulphantimonate of soda, Na Sb S3, 

 which only differs- from the common anti- 

 monate of soda. Na Sb Oa, by the substitu- 

 tion of sidphur for oxygen- 



Sulphur itself is inodorous, but many of 

 its compoimds possess a most offensive odor. 

 Tlie fumes of a burning match (sulphin'ous 

 anhydride) are familiar to every one, and 

 sulphuretted hydrogen has been described as 

 the "very essence of olfactory villainy." 

 It is this gas which is developed in a decayed 

 egg ; and it is abundant in certain mineral 

 waters which liave a widesprea<l reputation 

 for " strength," although it probably produces 

 no medicinal effect. A sulphur alcohol, mer- 

 captan (Cj II S,;) is, however, even niore 

 atrocioush fragrant tlum the gas, but. fortu- 

 nately, is only to be met with in the labora- 

 tory. Sulphur is easily electrified by friction, 

 and, if ground in a mortar, flies about, and 

 adheres to the pestle and sides so strongh that 

 it is necessary to moisten it with ;dcohol in 

 order to pulverize it. Its disinfectant and pre- 

 servative properties, especially of the product 

 of its combustion (sulphurous acid gas), are 

 well known, and its minor uses are very nu- 

 merous. Altogether it is a most useful and 

 valuable substance ; and its derivative, sul- 

 phuric acid, is one of the most important sub- 

 stances used in the arts. Fortunately the sup- 

 ply of this element is abiuidant, and we have 

 no cause to fear that it will ever be exhausted. 



PRACTICAL RECIPES. 

 To Prkvent Rust. — Melt together three parts 

 of lard and one part of resin in the powder. A very 

 thin coating applied with a lirush will preserve 



stoves and grates from rusting during summer, even 

 in damp situations. For this purpose a portion of 

 hlacklead mav he added. 



For Writinc; ox (jLAss. porcelain and metals. 

 Fabcr has introduced a composition consisting of 4 

 parts spermaceti, 3 parts tallow, and 2 parts wax, 

 melted together, and to which is added 6 parts of 

 either red lead, white lead, or prussian blue. The 

 mass is turned out in sticks. The marks can be ea- 

 sily rubbed out and save all labelling. 



Servickable Mortar. — Mortar made in the 

 following manner will stand, if used, in almost all 

 sorts of weather. One bushel of unslaked lime, 

 three bushels of sharp sand; mix one pound of alum 

 wiih one pint of linseed oil, and thoroughlj mix 

 this with the mortar when using it, and use hot. 

 The alimi will counteract the action of the frost on 

 the mortar. 



To Makk a Tioiir Fi.a.nge Joint. — To make 

 a flange joint that won't leak or burn out on steam 

 pipes, mix two parts white lead to one part red lead 

 to a stift" putty; spread on the Hange evenly, and 

 cut a liner of gauze wire — like mosquito net wire — 

 and lay on the putty, of course cutting out the 

 proper holes; then bring the flanges -fair." put in 

 the bolts and turn the nuts on evcnlv. 



To Make .\ Goi.n Soi.dkk. tlie following pro- 

 portions for 100 parts are recommended bv an ex- 

 change : — Silver. 54-74; gold. 11.94; copper, 28.17; 

 zinc, 5.81. Melt the first three metals together in a 

 covered crucible; when the cover is slightly cooled, 

 add the zinc a little in excess of the proportion 

 given, and stir up continually the alloy. This solder 

 runs very easily and is much esteemed by manufac- 

 turers. 



Etching Liqi id kor Steel. — Take i oz. sul- 

 phate of copper, 1-2 oz. of alum, and a half teaspoon- 

 ful of salt in a fine powder, and mix with a gill of 

 vinegar and 20 drops of nitric acid. The liquid 

 thus obtained m.iy be used for either cutting deepiv 

 into the metal, or for imparting a beautiful frosted 

 appearance to the surface, according to the time it 

 is allowed to act. The parts to be protected from 

 its action should be covered w ith beeswax or tallow . 



Be-WTIfii. Imitations of Mosaics. — Have one 

 side of plate glass roughened, or given a crystallized 

 surface, on which trace a design in suitable opaque 

 colors to represent the seams between the pieces 

 composing the mosaic. Fill in a portion with trans- 

 parent colours, then cover the whole surface with 

 gold-leaf, with a biicking of white and red lead, pa- 

 tent drier, and Jiipan gold-size, or anv material 

 which will protect the gold, such as amber dissolved 

 in spirit of turpentine. The eflect will he most re- 

 alistic. 



Fire-Proof Paint for Smoke-Stacks. — Slake 

 sufficient freshly burned quick-lime of the best qual- 

 ity. When the slaking is complete add sufficient 

 skim-milk, or water in its absence (though the first 

 is preferable), to make a liquid of the consistencv 

 of cream. To every 10 gallons of this liquid add 

 separately and in powder, stirring constantly, the 

 following ingredients in the order named; Alum, j 

 pounds; subcarbonate of potassium (commercial 

 potash will answer). 24 ounces; common salt, i 

 pound. If white paint is desired, the liquid needs 

 no further addition, though a few- ounces of plaster 

 of paris will improve the whiteness. Lamp-black 

 will give a number of shades from slate colored to 

 black. Whatever tint be used should now be in- 

 corporated, and the whole, after straining through 

 a sieve, should be run through a paint mill. When 

 ready to apply, the paint should be heated nearly 

 to the boiling point of water, and should be put on 

 hot. Fine white sand added to this paint makes it 

 a magnifioent covering for roofs and for crumhiinjf 

 brick walls, which it will protect perfectly. 



