[1854 



PROCESS FOR PRINTING COPIES OF PLANTS, MATERIALS, LACE, &c. 



307 



But in the course of experiments it was discovered that the 

 slight retardation was lessened, and for practical purposes obvi- 

 ated, by giving- a certain proportion to the breadth of the edge 

 of the index wheel and the tension of the springs (l-100th inch 

 to 13 ounces). A construction, only differing from that of Fig. 

 1 in some details, was therefore adopted. This is represented 

 in the woodcut, Fig. 3. In it the second toothed index wheel is 

 dispensed with, the single index wheel being increased in dia- 

 meter so as to read to 50 square inches, and in place of four 

 there are only three friction rollers. Instruments of this descrip- 

 tion have an accuracy amply sufficient for all practical purposes, 

 about double what has been noted above, and are of great value 

 in measuring enclosures on maps, especially those whicfti have 

 very irregular wavy outlines, effecting both an increase of accu- 

 racy and a great saving of labour and time over the old methods. 



Process for Printing copies of Plants, Materials, Lace, ifcc, 



from the originals, style*! (" Nuturselustclruck") 



^Natural Printing Process* 



Under this term, Louis Auer, of the Imperial Printing Office 

 at Vienna, has patented a process invented by himself in con- 

 junction with. Mr. Andrew Worring, overseer of the same 

 establishment, " for creating, by means of the original itself, in 

 a swift and simple manner, plates for printing copies of plants, 

 materials, lace, embroideries, originals or copies, containing the 

 most delicate profundities or elevations not to be detected by 

 the human eye," &c. A pamphlet giving a description of this 

 discovery and a series of specimens has reached us. The 

 examples consist of an impression from a fossil fish, from agates, 

 the leaves of trees, several plants, mosses, algse, and the wing of 

 a bat. These are all printed in the natural color of the objects 

 they represent; and it is difficult to conceive anything more 

 real than these productions. The general character of the pro- 

 cess is told in the following pithy manner by Louis Auer, in the 

 introductory paragraphs of his pamphlet : — 



" Query — How can, in a few seconds, and almost without 

 cost, a plate for printing be obtained from any original, bearing 

 a striking resemblance to it in every particular, without the aid 

 of an engraver, designer, &c. ? — Solution— -If the original be a 

 plant, a flower, or an insect, a texture, or, in short, any lifeless 

 object whatever, it is passed between a copper plate and a lead 

 plate, through two rollers that are closely screwed together. 

 The original, by means of the pressure, leaves its image im- 

 pressed with all its peculiar delicacies, — with its whole surface, 

 as it were, — on the lead plate. If the colors are applied to this 

 stamped lead plate, as in printing a copperplate, a copy in the 

 most varying colors, bearing a striking resemblance to the 

 original, is obtained by means of one single impression of each 

 plate. If a great number of copies are required, which the 

 lead-form, on account of its softness, is not capable of furnish- 

 ing, it is stereotyped, in case of being printed at a typographical 

 press, or galvanized in case of being worked at a copperplate 

 press, as many times as necessary, and the impressions are taken 

 from the stereotyped or galvanized plate instead of from the 

 lead plate. When a copy of a unique object, which cannot be 

 subjected to pressure, is to be made, the original must be 

 covered with dissolved gutta percha; which form of gutta 

 percha, when removed from the original, is covered with a 



solution of silver to render it available for a matrix for galvanic 

 multiplication." 



This process is also applicable to the purpose of obtaining 

 impressions of fossils, or of the structure of an ae;ate or other 

 stone. In all the varieties of agate, the various layers have 

 different degress of hardness; therefore, if we take a section of 

 an agate, and expose it to the action of fluoric acid, some parts 

 are corroded, and others net. If ink is at once applied, very 

 beautiful impressions can be at once obtained; but for printing 

 any number, electrotype copies are obtained. These will have 

 precisely the character of an etched plate, and are printed from 

 in the ordinary manner. The silicious portions of fossil and the 

 stone in which they are imbedded may in like manner be 

 acted upon by acid ; and from these either stereotyped or elec- 

 trotyped copies are obtained for printing from. We learn that 

 Mr. Bradbury, of the firm of Bradbury and Evans, has availed 

 himself of this invention, and that he is now preparing a scries 

 of Botanical specimens for publication, — so that, very shortly, 

 the public will be in possession of examples of this beautiful pro- 

 cess. It is not a little singular that the workers in German 

 silver and Britannia metal, at Birmingham, have for some time 

 been in the habit of ornamenting the surfaces of these metals 

 by placing a piece of lace, no matter how delicate, between two 

 plates, and passing these between rollers. In this way every 

 fibre is most faithfully impressed upon the metal. We are not 

 aware, however, that any attempts to print from these impres- 

 sions have yet been made at Birmingham. The value set on 

 the invention by the author may be judged by the following- 

 paragraph : — 



" Russia has given up Jacobi's application of the Galvanoplas-. 

 tic in the year 1837, and France the Daguerreotype for general 

 use in the year 1839; Austria has now furnished a worthy- 

 pendant to these two inventions." 



On the Consumption of Smolte.—Experiments witll Jukes's 

 Patent Furnace. By Mr. A. Fraser.* 



See page 310, 



•j- Erom the London Atbenteuin. 



The author stated that it was not intended to enter on the 

 various theories which have been advanced on the subject; or 

 to discuss the many inventions before the public, still less to 

 bring forward any new theory, but to give the " results of abso- 

 lute work," in a successful attempt to remove the smoke 

 nuisance from an extensive London brewery and its neighbour- 

 hood. Messrs. Truman, Hanbury, Buxton & Co. had tried most 

 of the plans which previous to 1847 gave reasonable hopes of suc- 

 cess. In 1847 the writer's attention was first drawn to Jukes's 

 patent furnace, which consisted of a strong cast-iron frame of the 

 full width of the furnace, and about three feet longer. The 

 fire bars were all connected together, forming, when complete, 

 an endless chain, and were made to revolve round a drum, 

 placed at each end of the frame, The front of the frame was 

 provided with a hopper, in which the fuel was placed, and a 

 furnace door, which opened vertically with a worm and pinion. 

 The height to which the door was raised by the stoker, regu- 

 lates the supply of coal, which was carried into the fire by the 

 gradual motion of the bars. This plan was first applied to an 

 engine boiler — a cylindrical one, with two tubes — driving a 40- 

 liorse power engine; and having been successful, it was adapted. 



* From the London Athen^um. 



