THE ALUMNI JOURNAL. 



273 



return, the Java planters must unanimously 

 agree not to supply more than half the bark re- 

 quired for the world's consumption. This is 

 estimated at 235,000 kilos of quinine sulphate, 

 so that Java shall only furnish bark for 1 17,500 

 kilos, which, taking 4 per cent, as an average 

 yield, shall be estimated as ?, 937, 500 kilos 

 of bark. The necessity for increased pay- 

 ment for the bark is seen by the fact that in 

 1894, Java furnished 5,293,750 kilos of bark, or 

 nearly sufficient for universal consumption. If 

 these arrangements end in a contract, the 

 French and American manufacturers, together 

 with other English and smaller manufacturers, 

 will be unable to obtain upon the market any 

 but Indian, Ceylon, American and African bark. 

 This would, of course, lead to a marked advance 

 in the price of quinine, but whether the negotia- 

 tions will be brought to a successful issue or 

 not remains to be seen. — The British and Colo, 

 nial Druggist . 



Smoke. — The following from the American 

 Engineer and Railroad Journal, seems worthy 

 of mention : A mistaken idea exists as to the 

 amount of actual carbon contained in those 

 dense masses of smoke which are seen rising 

 from the tall stacks of manufacturing and other 

 large plants. By passing through water the 

 gases arising from a furnace burning bitumin- 

 ous coal, and weighing the solid particles re- 

 tained or precipitated, it has been proved, it is 

 claimed, that they amount to less than six per 

 cent, of the total amount of coal consumed. It is 

 not strange that a different idea is entertained 

 of the quantity of actual carbon seemingly going 

 to waste, when the wonderful coloring power of 

 the finely dividing particles of carbon is con- 

 sidered. To prove this, it is only necessary to 

 try the well-known experiment of smoking a 

 bit of glass with a candle, and then mixing up 

 with a palette knife a portion of the coloring 

 matter thus secured with a drop of two of gum 

 arabic. A very small portion of this mixture 

 will color many quarts of water. The actual 

 carbon contained in the smoke itself is inappre- 

 ciable, but the unconsumed invisible gases in- 

 variably associated with the smoke are consider- 

 able in quantity and indicative of a financial 

 loss much larger than is generally known. — The 

 Popular Science Monthly. 



To Measure Shades of Color. — In a number 

 of industries, preparing printing inks, color il- 

 lustrations, mixing dyes, estimating the quality 

 of petroleum, lard and flour, detecting the con- 

 dition of steel in a Bessemer converter, and so 



on, it is of great importance to measure very 

 delicate shades of color most accurately. As 

 the result of twenty-five years' study of the 

 problems involved and experiments with 

 various methods of dealing with them, J. W. 

 Lovibond, of Salisbury, England, has invented 

 a device which is said to perform the desired 

 work easily and accurately, although any one 

 employing it successfully must, of course, pos- 

 sess a keen sense of color. In two tubes, placed 

 side by side for comparison, are placed the ar- 

 ticle to be tested (either a powdered pigment 

 or a liquid preparation) and a number of trans- 

 parent colored glass plates. The latter are 

 properly selected and added until the light 

 transmitted through them exactly matches the 

 hue of the dye or pigment ; and then the num- 

 bers are read off from the plates and summed 

 up, very much as one would ascertain the 

 weight of an article by a set of sensitive scales. 

 Standards having once been secured for each 

 of the three primary colors (red, yellow and 

 blue), more than 100 different degrees of in- 

 tensity in each color are obtained in as many 

 different plates or disks. By properly propor- 

 tioning and mixing those representatives of the 

 fundamental colors all the possible tints and 

 hues that the eye ever saw can be reproduced 

 exactly. A record of the disks used in so doing 

 having been made, it is possible to transmit 

 merely a numerical memorandum instead of 

 samples, to ascertain whether subsequent pur- 

 chases are up to the original standard, and to 

 detect any fading or change of hue owing to 

 time and exposure. Mr. Lovibond calls his in- 

 strument the " tintometer." — The Pharma- 

 ceutical Era. 



Color Photography. — At a recent soiree of the 

 Royal Society, in London, Dr. Joly, of Dublin 

 exhibited some photographic transparencie 

 upon glass plates representing various objects 

 in their natural colors. The subjects photograph- 

 ed, were especially chosen because of the variety 

 of color and delicate shading, and were repro- 

 duced with great naturalness and fidelity. The 

 results were accomplished by the use of a finely 

 ruled glass plate, two hundred to three hundred 

 lines to the inch, each three lines being a com- 

 plete color series, consisting of an orange-yellow 

 line, a greenish-yellow line, and a blue-violet 

 line; these colors being repeated over and over 

 again. The lines are ruled with colored 

 inks, made up of gum and gelatin mixed in 

 certain proportions on a gelatin-coated plate. 

 The plate to be exposed is placed in contact 



