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THE CIVIL ENGINEER ASD ARCHITECTS JOURNAL. 



r March, 



Mr. Tennant stated the specimen of gnid exhibited by Mr. Walls was 

 evidently a water ivor.n fragment. Tiie gold is usually found in small grains, 

 which are obtained by washing the alluTial soil. He also exhibited a speci- 

 men of gold which at the time he had purchased it (about two months be- 

 fore) was the finest specimen of pure native gold he had seen ; it contained 

 nineiy-two per cent, of pure metal, A reason he had for purchasing the 

 specimen was, because it had some of the alluvial soil attached to it ; and 

 io that soil he imagined that one or two small diamonds might be detected, 

 and was most anxious to ascertain that fact, as he had stated to the Society 

 last session, in a paper, that diamonds, and other precious stones, might be 

 found in tlie gold districts of California; and that such gems are being 

 thrown aside, although the refnse diamonds sold to the lapidary to be broken 

 np are worth 50/. per ounce, while gold is not worth more than 3f. 15s. He 

 had not, however, been able to discover any diamond ; but, on examining 

 the soil ^^■ith the microscope, he had detected some small crystals of garnet, 

 two grains of platinum, and several of quartz, &c. In looking over a quan- 

 tity of other gold specimens, he had found quai tz in great abundance, and 

 it had evidently formed the original matrix of the gold. He next called at. 

 tention to tbe fact, that gold is not generally found in the position in which 

 it was originally deposited. Mr. Tennant urged on the attention of persons 

 about to visit the gold districts the necessity of making themselves ac- 

 quainted with tbe few simple rules which should guide them in their search 

 for gold, and other minerals, and which were published in the Society's Cir- 

 cular last session. 



Mr. Hopkins stated that there was nothing unusual in the gold deposits 

 of California. The gold was found precisely under similar circumstances at 

 the deposits of the Ural in Russia, and some other places. When the west 

 tributaries of the Sacramento and the 5an Joachim have been washed, Call- 

 fornia will doubtless be brought to the ordinary level of large gold-producing 

 countries. He was of opinion that metals were formed in the crystaUine 

 rocks in flakes, masses, crystals, arborescent, &c., according to the degree of 

 the electro-chemical action, and that this action in the moist crystalline 

 rocks in situ was as constant as the growth of vegetation. Tbe surface pro- 

 ducts and the veins, he said, were formed on the same principle. He per- 

 fectly agreed with the remarks that were made, that those called geologists 

 and others, who have been led to suppose that such products were the result 

 of volcanic action, were totally wrong. In fact, true practical and useful 

 geology was known only to a few persons who have studied amongst the 

 great woiks of nature. Mr. Hopkins concluded by stating that gold is ge- 

 nerally found in tbe debris of feruginous granites and porphyries, and that 

 tbe quanuty of gold to be obtained depends on the elementary composition 

 of the granitic rocks, the complete satnration to induce chemical action, so 

 as to cause a kind of efflorescence of the metals into all joints, vacuities, 

 &c., and the oxidation and disintegration of the superficies. In fact, be 

 said that the superficial decomposition of the moist and friable auriferous 

 rocks were more or less constant, the degree of action and the accumulations 

 at tbe foot of tbe mountains being dependent solely on mineral and physi- 

 cal conditions confined to no age of rocks nor to any particular zone ; and 

 that this electro chemical agent was constantly providing inexhaustible 

 stores of mineral wealth for successive generations. When the decomposed 

 and frialjle surface is washed down to tbe ravines and plains, he said, the 

 gold and other heavy ingri'dients, especially the black titaniferous iron (the 

 usual companion of the precious metal), were deposited in pools and other 

 places, presenting obstacles to their descent, and consequently those places 

 have become enriched hy concentration, tbe lighter particles being constantly 

 washed away ; and that this was the origin of the riches of the tributaries 

 of the Sacramento. 



ROYAL SCOTTISH SOCIETY OF ARTS. 



Jan. 14. — Thomas Grainger, Esq., President, in the Chair. 

 The following communications were made: — 



" Verbid Statement on the relative value of Chlorine, Nitric Acid, Sul- 

 phurous j'icid, and Ozone, as disinfectants ; and on the best metliod of apply- 

 ing ttiem to destruction of Contaijious Matters,^* By George Wilson, M.!>. 

 The author dwelt at length upon tbe relative value and best mode of 

 applying, as disinfectants, tbe difl'trent substances mentioned in the title of 

 his paper. A chief object of tbe communication was to draw attention to 

 tbe alleged virtues of ozone as a purifier of the atmosphere, and to notice 

 that, in defect of any other disinfectant, ozone might be generated in apart- 

 ments, the air of which was vitiated by animal exhalations. The simplest 

 process for this purpose would Ije the exposure of moist phosphorus to air; 

 but an electrical machine or voltaic battery might also be used. Tbe other 

 point at which the author aimed was to show the unwise neglect of the sul- 

 phurous acid as a disinfectant, or rather antiseptic, which had been practised. 

 It appears, according to Dr. Wilson, that in the wine countries this gas is 

 employeil to arrest the acidification of the weaker wines; that in the Man- 

 chester Dye Works it is found more ethcacious than chlorine in destroying 

 tbe otfensive odour which attends the employment of cochineal ; and that at 

 paper nulls it is employed with great success to prevent the putrelaction of 

 the scrolls or clippings of the sliin used in tbe manufacture of tbe paper size. 

 The author acconliiigly strongly recomiuended sulphurous acid as a cheap 

 and powerful deodoiiser and disinfectant. 



"Remarks on the Philosophy of the Beautiful; and an Analytis of the 

 principle of Proportion, as applicable to Arcliiteclure." (Hart I.) By 

 David Cousin, Esq., Architect. 



The author coiuhated the definition of the beautiful, as laid down by the 

 late Mr. Alison and Lord Jeffrey, and held that beauty was recognised hy the 

 mind in particularybrms, independently of any association connected with 

 tbe object which it admires. This first part of the communication was 

 entirely metaphysical, and cannot well be given in abstract. The author 

 will read at next meeting, the second or practical part of his paper, showing 

 how Mr. Hay's principles of proportion, determined by angles bearing har- 

 monic ratios to each other, can be applied to architecture. 



Jan. 29. — A paper was read by Mr. Meik, C.E., of Sunderland, upon "A 

 New Self Registering Tide Gauge, lately erected and now in operation at 

 Sunderland Harbour^" which was followed by a paper read by Mr. Hi;nry 

 Watson, of Newcastle, describing "The Application of Prepared Gauze, by 

 which means the Gauge is observable by Night as well as Day" a very 

 important desideratum, 



Tbe merits of Mr, Meik's paper consisted in directing particular attention 

 to the necessity of all ports and docks having conspicuous gauges for the 

 guidance of vessels inward or outward bound, and of those gauges being of 

 the most simple and intelligible description. Mr. Meik had prepared, and 

 showed in juxta position, the present signals used at Leitb, and those brought 

 forward by liira. For the information of our readers we may mention, that 

 tbe signals used at Leith consist of a series of balls and flags which have to 

 indicate to seamen the depth of water. The new gauge, at a single glance, 

 shows tbe height of the tide in feet by a number in figures corresponding to 

 tbe depth of water on the bar of a harbour or entrance to a dock. The 

 little attention we often find paid by seamen to the preservation of their own 

 lives, shows the great advantage of having figures that can be at once easily 

 understood, without consulting books, and thereby incurring a loss of time, 

 which in many cases results in the loss of valuable life and property, Mr. 

 Meik proceeded to show that a gauge having the property of being easily 

 understood by all as " soon as seen," had been erected by himself, in con- 

 junction with Mr. Watson, for the Commissioners of tbe River Wear at Sun- 

 derland Harbour, He then read tbe following description, which was illus- 

 trated by drawings : — 



A well, carefully boxed in, and of exactly similar depth to the water on 

 the bar, is made below tbe building which contains tbe apparatus. Within 

 this well, in an interior pipe or trunk, and rising and falling with the tide^ 

 works a float suspended by a copper wire cord, which is carried over a spiral 

 cone fixed in an upper story of the building. By the simple arrangement of 

 a wheel and pinion at the opposite end of tlie axle to which the cone is 

 fixed, a web of wire gauze works on two rollers fixed at the upper and lower 

 ends of the web. The lower roller is regulated by the movement of this 

 wheel and pinion, the upper one by a babince weight attached to a copper 

 wire cord, which also passes over another spiral cone, having at tbe extremity 

 of its axle a second wheel and pinion similar to the first. As the float rises 

 and falls with the tide, tbe wheels and pinions connected with the cones, 

 over which the cords of the float and balance weight respectively pass, 

 move tbe rollers on which the gauze web travels. On this web are painted 

 in large figures the various depths from high to low water; and as tlie web 

 works, two points upon it indicate the number of feet and half-feet on the 

 bar at any hour of the tide. 



The web and the figures on it can be made of any size, and to travel 4, 6, 

 8, 10, or any other proportion, to 1 of the float, by regulating the size of the 

 wheels and pinions. 13y day tbe figures on the web are shown white on a 

 black ground; by night they are brilliantly lighted up, tbe ground still 

 remaining dark, A white transparent varnish is used for the figures, and an 

 opaque black for tbe ground. The illumination by night is so steady and 

 powerful, that the figures, if made large enough, and the apparatus fixed at 

 a sufBeient elevation, will be visible at a considerable distance at sea, and 

 thus afford vessels the means of knowing the exact depth of water, at the 

 mouth of any harbour, before entering it. This simple piece of niecbanism 

 is applicable to all places where the want of a correct and conspicuous gauge 

 has been felt, not only in harbours and docks, but at railway stations for sig- 

 nals, and such like purposes. The apparatus used occupies so liitle space, 

 that it can all be contained and worked in a column or pillar without any 

 other building, 



Mr. Watson read a paper describing more particularly the preparation o 

 the wire gauze, and exhibited a neat specimen, which, although small, fully 

 and clearly illustrated the novelty and utility of the application. 



INSTITUTION OF CIVIL ENGINEERS OF IRELAND. 



Feb. 8— Lieut.-Col. Harry D. Joses, R.li,, President, in the Chair. 

 The following papers were read :— 



" A Description of the Viaduct, near Quaker's Yard, Taff Vale Rail- 

 ' way. South Wales," By Mr. S. Downing, Assistant Piolessor of Civil 

 Engineering in Irinit) College. 



This viaduct was designed by Mr. Brunei, to carry the main line of the 

 railway over the river TaB, at a point where, from the nature of the loca- 



