1855.] 



STEAM AS AN INDUSTRIAL AGENT. 



315 



race, named by him Allopbylians. Dr. Pi'icliavd maintains that the 

 religion of these AUophjiian tribes was Fetishism, and mainly consis- 

 ted in the employment of spells and incantations, without any hope or 

 fear of a future state in which there should be retributive justice. 



It is a curious fact on a small scale, that the teeth in these Allophy- 

 liau crania are uniformly found perfect and unchanged. Animals that 

 live nearly entirely upon flesh may to this day generally be observed 

 to preserve their teeth in like manner to old age. But the cause of 

 the exemption of these aboriginals from toothache may have been 

 partly the shortness of theii' lives, and partly the prevalence of hunger 

 and absence of dyspepsia. 



To the stone period succeeded that of the Bronze. This country 

 has from time immemorial been famous for her mines of copper and of 

 tin. There can be no doubt but that the Tin Islands of Herodotus re- 

 ferred to Cornwall and its adjacent islets, and that the Phoenicians 

 visited them for the sake of their important metals. We can even 

 trace indications of these visits in the earliest British coins, which 

 have a Phoenician construction. Implements, weapons, and utensils 

 of bronze were probably first obtained from the foreign visitors, but 

 ultimately our forefathers would learn to construct them for them- 

 selves; and in the remains of this bronze formation, in which, however, 

 no iron is to be found, we perceive evidences of an extended civiliza- 

 tion, a greater amount of comfort, the possession even of luxuries, 

 and of an increased development of intellectual attainments. 



Thus the men of these islands no longer dwelt in underground holes, 

 but erected structures from the spoils of the adjacent forest. The 

 cleared spaces would give opportunity for the hunter to practise the 

 art of the husbandman, and his new alloy would afford him the means 

 of tilling the soil. The weapons used in war became, if not more deadly 

 than the old stone ones of sling-balls, more elegant, and we perceive 

 weapons of defence as well as oifence. Of this latter kind, the more 

 common remains are those of shields, uniformly round, and with bosses 

 in the centre. The domestic utensils formed of bronze, or rather the 

 remains of them, show considerable art and refinement : and to this 

 class, along with those of bronze, we must now associate some of 

 pottery. Personal ornaments too assume a degree of elegance that 

 strongly contrasts with the oyster necklaces of the rude inhabitants of 

 the stone period, and we learn from such of these as we find lying in 

 the ground of the bronze formation, that those who dwelt here during 

 its deposition were also acquainted with gold and silver. Perhaps 

 the greatest indication of all, of the improved civilization of the men of 

 this formation, is the fact of inscriptions occurring on their sepul- 

 chi'al monuments. The men of the stone time were bui'ned without 

 any indication that their course was not altogether run, but those of 

 the bronze period were even after dead still represented as linked up 

 with human aspirations and futurity. Last of all, we trace in the re- 

 mains of this period, preponderance of female ornaments, indicative of 

 women having attained a higher social position. 



From this we come to a new formation, containing relics of man 

 along with worked iron. We have not space to dwell upon its charac- 

 teristics ; — the many uses to which that metal was put, — the signs of 

 the subjugation of the horse, — the evidmce of the existence of strong- 

 holds — of the greater cranial development of the skulls, or of the ap- 

 pearance of the true Celtic head. We are able to trace the dying away 

 of this formation, and of its passing into the tr.aditional histories, the 

 times of Macbeth and his wife Gruach : St. Patrick, St. Keornan, and 

 the Northmen. Then we come to the days of history. 



Even in these (geologically speaking) recent times, the transition of 

 land to sea, and of sea to hand, has in Scotland been considerable. 

 For example, ten yards under the surface of the present canal of Fal- 

 kirk, and far removed from any navigable stream, a canoe was found. 

 N.ay, in the same district, when constructing the Union Canal, the 

 skeleton of an elephant was discovered, pointing perhaps to land com- 

 munication long since destroyed. At the distance of a mile from the 

 Frith of Forth, the bones of a wh.ale were discovered, with a bone 

 harpoon in tlicm. Still more recently, another whale's skeleton with 

 another harpoon was found seven miles farther inland, on what is 

 now the Blair Drummond estate. Analogous remains have been dis- 

 covered about the valley of tlie Clyde, all of which go to prove that it 

 too was once the bed of an extinct estuary. Other relics in other lo- 

 calities tell the same talc for their districts, and show us that the geo- 

 graphical appcar.ances of Scotlaml have been greatly changed, and 

 that former seas have bocoino dry laml, as also former lands have pro- 

 bably become sea-beds. 



FciTuanent Impressions of Flowers on Glass.* 

 Mr. Robert Smith of Blackford, who has often contributed to oui- 

 pages, has contrived a very ingenious and effective plan of ornamenting 

 glass, by producing thereon, permanent impressions of flowers, leaves 

 of plants, and other objects. In this process of ornamentation, the 

 operator goes to work by first preparing the objects to be reproduced 

 on the glass surface with a solution of gum. The details of the figure 

 are thus attached to the glass, in the positions required by the device. 

 The entire face of the glass thus treated, is then covered over with a 

 composition of oil, tallow, and wax, in a warm state. When this com- 

 position coat becomes solid, the objects are removed from the glass, 

 which is now submitted to the action of fluorine gas ; or liquid fluorine 

 may be poured upon the glass ; or further, the plate may be treated 

 with fluor spar and sulphuric acid. This is the ordinary treatment 

 involved in glass etching — the peculiarity of Mr. Smith's process being 

 the mode iu which the design or the line of action of the acid is pro- 

 duced. The fluorine corrodes the glass only at the parts where the 

 flowers or pattern objects have been placed, and hence the forms of 

 the objects, however elaborate or delicate, are faithfully reproduced 

 from the models supplied by nature herself The ornamental designs 

 produced in this w.ay are extremely beautiful, contrasting as strongly 

 with the result of ordinary staining, as does a good daguerreotype 

 picture, or nature painting, with a mechanically produced engraving : 

 the figuring accomplished in this way may be coloured as fancy sug- 

 gests, by the common process of baking or "burning-in" in a furnace. 

 This is another of those processes, by which we are now compelling 

 nature to reproduce for us her choicest devices in a more enduring 

 form. 



Steam as an EndiLStrial Agciit,'^ 



Mr. William Fairbairn, whose great services in developing mechanical 

 science can never be ovei-looked or forgotten in any quarter of the 

 world where mechanical talent possesses rank at all, has just given ono 

 more proof of his attention to the exigencies of the times, by delivering 

 two elaborate lectures at the Manchester Mechanics' Institution, on 

 "Steam, its Properties and Application to the Useful and Industrial 

 Arts." In that great centre of steam power, such a subject, com- 

 mented upon by such an authority, and coming, too, in the wake of 

 the movement there making to secure a better system of steam super- 

 intendence, was certain of meeting with more than ordinarj' attention; 

 and we are glad to find that the lecturer's efforts were duly appreciated 

 by the large audiences assembled to meet him. In that portion of 

 his discourse which related to boilers, he stated that the cylindrical or 

 spherical was the most eligible and the strongest form in which iron 

 plates would resist internal pressure. The deduction for loss of 

 strength, on account of riveted joints and the position of the plates, 

 was about 30 per cent, for the double riveted joints, and 4i per cent, 

 for the single ones ; the strength (calling the plates 100) being in the 

 ratio of 100, 70 and 56. He found that 31,000 lbs. to the square inch 

 was the ultimate strength of boilers having their joints crossed and 

 soundly riveted. Flat surfaces, frequently essential, were not so 

 objectionable with respect to strength as they appeared to be at first 

 sight, but when properly stayed, were the strongest part of the 

 construction. This was proved by the result of experiments made on 

 the occasion of the bursting of a boiler at Longsight. Two thin boxes 

 22 inches square and 3 inches deep, were constructed. One cm res- 

 ponded in every respect to the sides of the fire-box of the exploded 

 boiler, the stays being in squares, 5 inches asunder, and the sulc 

 containing IG squares of 25 inches area. The other contained 2.J 

 squares of IG inches area, the stays being i inches asunder. One side 

 of both boxes was a copper plate .Much thick ; and the other side of 

 both an iron plate three-eighths inch thick. To those the same valve, 

 lever, and weight were attached, and the pumps of an hydraulic press 

 applied. That divided into squares of 25 inches area, swelled -OS-incU 

 with the eighth experiment, at a pressure of 455 lbs. to the square 

 inch. At the nineteenth experiment, with a pressure of 78a lbs. to tho 

 square inch, the sides swelled -OS-inch; and at a pressure of Slu lbs. 

 the box burst by the drawing of the head of ono of tho stays through 

 the copper, which, from its ductility, offered less resistance to pressure 

 in that part where the stay was inserted. Tho tenth experiment, with 

 the other box of 10 inch areas, resulted in a swelling of -Ol-mch. the 

 pressure being 515 lbs. to the square inch. At OOo lbs. the swelling 

 was -OS-inch, and from that point up to ]2t)5 lbs. the bulging was 

 inappreciable. With the forty-seventh experiment, at a pressure of 



" From tliK I»lnlon rrjcllc.il Jlccb. .ToumiO, April, 1865. 



