228 



NATURE 



\7uly 19, 1877 



a complete explanalion of the phenomena exhibited by certain 

 Japanese mirrors 'throvn h ? mistake as to their nationality I called 

 them Chinese) ; and ss your readers appear to be unacquainted 

 with this, perhaps I may be allowed to reproduce the substance 

 of my former letter. In order to ascertain whether any varia- 

 tions in the form of the surface of the mirror, which was very 

 slightly convex, affected the question, I looked for any distor- 

 tions that might be produced in the image of the ground-glass 

 globe of a gas lamp, as the point of incidence moved across that 

 portion of the polished surface on the back of which was a raised 

 figure. Let A and v, be two lines on the surface immediately 

 over the two edges of such a figure. Then as the limb of the 

 image approached A, it became flattened ; when it had passed a 

 it expanded to more than its original size ; indeed between A and 

 B the image was sensibly larger than when viewed from any other 

 part of the mirror. When the limb approached R it was again 

 flattened, and beyond r. it resumed its original dimensions. 

 This clearly proves that the portion of the surface of the mirror 

 between A and B was, if not actually plane, at least less convex 

 than the rest of the surface ; and as upon this supposition the 

 figures when thrown upon a screen should appear hrii;h(e)- than 

 the rest of the image, which is exactly what occurs in fact, there 

 can be no doubt that this is sufficient to account for the 

 peculiarity in question. In all probability the mirror had 

 warped in coolin?, except in the thicker portions where the 

 raised figures existed. J. Parnell 



Hadham House, Upper Clapton, July 6 



Printing and Calico Printing 



Your correspondent, Mr. Henry Cecil, is under a singular 

 misapprehension as to the inventor of cylinder machine calico 

 printing, and the date of its first practical application. Mr. Isaac 

 Taylor was certainly not the originator of cylinder printing ; and 

 that art was developed long "before he, "in 1855 or 1856 

 superintended its application at Manchester." Mr. Taylor, it 

 is true, obtained several patents for inventions connected with 

 cylinder-printing— one, I think, for a form of pentograph, and 

 another for the use of thin sheet copper instead of thick cast 

 cylinders of that metal. These, so far as I know, never 

 -succeeded in practice, and it is highly probable they brought 

 their gifted inventor loss instead of gain ; but that result was 

 not due to "the inevitable compliment of piracy." Who the 

 inventor of cylinder printing was it would be hard definitely to 

 determine. Nearly a century and a half ago a patent was granted 

 for an invention which embodied the 'leading principles of the 

 modern machine, and from that time downwards the apparatus 

 gradually developed and perfected in the hands of innumerable 

 practical inventors. 



The Writer of Calico Printing in the 

 "Encyclopedia Britannica" 



LOCAL MUSEUMS 



THE importance of local museums is gradually but 

 unmistakably forcing its ;lf upon the country. It 

 may take much time to foster any united action, without 

 which any definite progress is very improbable, but year 

 by year is adding to the ranks of those who are wise 

 enough to see and have influence enough to advocate 

 their value as a part of the educational stock-in-trade of 

 the nation. We rejoice to see that Mr. Chamberlain has 

 enrolled himself among their advocates in the House of 

 Commons. On Monday he drew attention to the fact 

 that the public expenditure for the promotion of science 

 and art was exclusively confined to London, Edinburgh, 

 and Dublin. The amount of the estimate this year, he 

 said, for museums, art galleries, and parks in the me- 

 tropolis amounted to nearly 400,000/., and that for 

 Edinburgh and Dublin to nearly 50,000/. To those sums 

 the provinces had to contribute twice over. Birmingham 

 contributed about 4,000/, and had to find about 8,000/. 

 a year besides for her own local art institutions. It 

 might be said with truth that a ntitional collection 

 should be placed in the metropolis at the expense of 



the nation, but that argument did not apply to the 

 expenditure on the public parks and still less to that 

 which the Bethnal Green IVIuseum involved. He did 

 not complain of such expenditure. It produced most 

 admirable results, adding as it did to the pleasure 

 and happiness of great masses of the people, and tending 

 to elevate and refine their minds. It was, too, in some 

 sort a commercial investment, as it was calculated to 

 enable artisans the better to compete with those of other 

 nations. What he complained of was that the principle 

 had not been carried far enough. He was anxious to see 

 established in every one of our great centres of population 

 and industry museums devoted to art and manufactures 

 appropriate to each particular district. To show how 

 highly these institutions were appreciated in the provinces, 

 he mentioned that in Birmingham the local museum 

 which had been established by private subscriptions was 

 visited annually by 300,000 persons, and as the population 

 of the town was only 370,000, the attendance was 

 immensely greater than was shown by the returns of the 

 number of visitors to our metropolitan institutions. 

 Results equally extraordinary could be quoted from other 

 provincial towns in which such museums existed. He 

 further stated that although provincial communities were 

 at present legally able to tax themselves to the '.xtent of 

 \d. in the pound for the purpose of establishing museums 

 and libraries, in Birmingham all this money went to 

 the free library, and they had therefore no means of 

 establishing an industrial museum. 



We are glad also to see that the Government is now 

 alive to the importance of this action, for, although Lord 

 Sandon in his reply begged that the matter might not be 

 pressed upon them at the present moment, he reminded 

 the House of the great advantage which the country 

 derived from the South Kensington Museum, which was 

 now, in fact, a gigantic circulating museum. Almost all 

 the principal objects in the museum, except those of 

 great rarity or delicacy, were sent on their travels at 

 different times through the provinces, and in this way 

 aid was already given to local museums. The country 

 derived enormous advantage from this vote. Local ex- 

 hibitions were frequent, and loans from the South 

 Kensington Museum for these exhibitions were very 

 numerous. Eight museums had these objects sent to 

 them, and a great deal had been done as the hon. gentle- 

 man wished. The South Kensington authorities were 

 anxious to follow that course, but he could not say 

 Avhether they would be able next year to do more in 

 that direction. Their hands were to some extent tied 

 by the necessity of economy, but the matter would 

 receive the best attention of the Government, and 

 he hoped that next session they might be able to go 

 further. 



Of course, neither Mr. Chamberlain nor Dr. Lyon 

 Playfair allowed the subject to drop without pointing out 

 that the British Museum and the National Gallery had no 

 circulating system in operation, that in fact Lord Sandon 

 was quite justified in adopting that line of argument with 

 regard to the South Kensington authorities ; but that 

 many of the London galleries and museums were of no use 

 to the provinces. The Britisli Museum, for instance, and 

 the National Gallery were practically of no use except to 

 London, yet every one knew that they contained many 

 duplicates which would be most valuable to the provinces, 

 and the offer of some important pictures was sometimes 

 declined on behalf of the National Gallery. Nor was this 

 all. Dr. Playfair pointed out th.it in France the Minister 

 of Education was responsible for all the museums, and 

 constantly sent collections into the provinces ; but in 

 England, the management of the galleries was, so to 

 say, dislocated, and not under one authority or one 

 Minister. Why did he not go further and point out 

 the recommendation of the Duke of Devonshire's Com- 

 mission ? 



