KNOWLEDGE. 



Jl-ne, 1911. 



dilution of vinegar, and a cheap vinegar containing 

 3-5 per cent, of acetic acid is often sold under the 

 name of " Diamond." .\ recommendation was 

 recently made. ho\\ever. in a report to the Local 

 Government Board that vinegar containing less 

 than 4 per cent, of acetic acid should not he sold, 

 and tlu're is 'a general tendency on 

 vinegar manufacturers to accept 

 this standard, which has been 

 upheld in undefended cases in 

 the ])olice courts. 



With regard to what should 

 be the composition of the other 

 constituents in vinegar, there 

 is no agreement either among 

 manufacturers themseh-es or 

 among scientific authorities. 

 Should malt vinegar be brewed 

 entirely from malted barle\-. or 

 is any sort of malted grain 

 ])crmissible ? According to the 

 ohl Pharmacopoeia malt vinegar 

 was to be brewed from a 

 mixture of malted and unmalted 

 grain, and if this is accepted. 



rice must be regarded as quite as admissible as 

 barlew .Again, maize is largeh- used bv vinegar 

 makers, but the opinions of authorities differ upon 

 the [joint whether glucose derived from maize is 

 I)ermissil)le. 



.-Ml these variations in the materials used 

 affect the hnal composition of the solid matter 

 in the vinegar, and prevent the analyst from 



drawing deductions as to the origin of the (iroduct. 

 Thus a vinegar made entireh- from malt will 

 contain a considerable proportion of phosphates and 

 nitrogenous substances, whereas in a rice \'inegar the 

 amounts of these constituents will be verv much 

 less, and. in the absence of special knowledge to the 

 the part of contrar}', such a \'inegar might verv well be certified 



as containing added acetic acid. 

 The so-called "wood vinegar," 

 which consists of acetic acid 

 obtained by the destructive 

 distillation of wood and coloured 

 with caramel, is a perfectlv 

 wholesome article, and no ob- 

 jection need be taken to its 

 sale under its own name. The 

 legitimate vinegar maker has, 

 however, to meet the competi- 

 tion ()f the " vinegar faker," 

 will I with the aid of no other 

 plant than a barrel of acetic 

 acid and a keg of caramel, is 

 able to put uj)on the market 

 a product which he sells at a 

 cheap price under such titles as 

 " Double refined malt vinegar." The occasional prose- 

 cution of the retailers of these concoctions does little 

 to check the evil, for the "manufacturer" promptly 

 leaves his "works." usualh' a back vard. and cannot 

 be found. It is not long, howexer. before he 

 re-apjiears under another name, and continues to 

 meet the popular demand for "pure malt vinegar" 

 at a price at which it Cduld not possibly be made. 



Figure (?. 

 Section of Upper I'art of a Modern .\cetifier. 



NOTICE.S. 



.\ Xi:\V l'110Xl>GK.\I'H.— M. Lifschit^. ayoting Knssian 

 scientific man now working in Paris, has invented a phonograph 

 which uses photography for recording the \ibrations of human 

 voice. 



He began his experiments in Russia but has continued them 

 in M. Dastre's laboratory at the Sorbonne, and there a 

 demonstration has been given before a small gathering of the 

 friends of science with a rough model constructed by the 

 inventor and M. Victor Henry. 



The sonorous vibrations of the voice striUing a membrane 

 are thrown in the form of luminous images by a small mirror 

 upon a sensitive photographic film travelling at a high speed 

 as a band, and describe a curve upon it. Where the light 

 acts on it. the film is rendered hard and insoUiblc. The 

 other parts remain soft, and may be washed away. 



For reproducing the voice the band passes before a " fente " 

 behind which is a chest of compressed air. .As the hollows of 

 the curve move rapidly before the " fente " the air as it 

 escapes reproduces the vibrations which caused them — in 

 other words it reproduces the vibrations of the human voice. 



The word " curve " is used here in its scientific sense. 

 There are. in fact, "' makes " and '" breaks." Theoretically, the 

 membrane which actuates the mirror may be dispensed with. 



M. Dastre is convinced that the new phonograph when 

 properly constructed, will give results far above those yielded 

 by mechanical phonographs of the lidison type. 



Photographing vibrations is not new. What is new is the 

 combination of principles and the method of reproducing the 

 results of the photography. ., .- .. 



STUNVHLKST COLLEGE UBSEKN ATOKV. — The 

 Report of the Director, Rev. W. Sidgreaves, S.J., F'.R.-A.S., 

 for 1910. just to hand, shows a good record of work. It was 

 found that " the year's mean barometric pressure was a little 

 below the average, and of the month means only those of 

 March, September and October were above their respective 

 averages. These also were the drier months, the only ones in 

 which the rainfall was below the monthly average. But the 

 duration of sunshine was less than the average in September 

 and October. The highest reading of the barometer occurred 

 in March, and the lowest in F'ebruarj'. The former was a fine 

 dry month, the latter remark.able for its number of rainy days, 

 the greatest number recorded for F'ebruary in sixty-three years." 

 During the same period no January has shown so great 

 a rainfall as this, 8-043 inches, nor so great a fall in one day 

 as on the 15th. when 2-07 inches were recorded. Of the one 

 hundred and sixty-six days on which the Sun w-as observed 

 the disc was free from — presumably dark — spots on no less 

 than forty, and drawings were made on the remaining one 

 hundred and twenty-six. The mean daily area covered by 

 spots II being equivalent to 5n\,f)th of the visible surface! fell 

 from 3-8 in 1909 to 1-S in 1910. It is, however, remarkable 

 that the daily declination range of the magnetic needle 

 increased from 13-5 in 1909 to 14-5 in 1910. During the 

 year no %ery great magnetic disturbances were recorded, 

 though January 25th, March 27th, 2Sth and 30th, April 1st 

 and 27th. June 8th, 19th and 20th, .August 9th, 21st. 22nd and 

 28th, September 29th, October 4th, 6th, 12th and 27th, and 

 December 2Sth, are all recorded as great. ,. .- ,^ 



