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c r e a t e d b y t h e outrushing air which dragged microorganisms f r o m t h e surrounding air o n t o t h e plate. In order t o eliminate t h i s undesirable effect we tried fasteni n g funnels of various sizes b y m e a n s of a r u b b e r a t t a c h m e n t t o t h e cock. We f o u n d t h a t a funnel whose circumference was exactly t h a t of our dish gave u s t h e best results so t h i s m e t h o d h a s been a d o p t e d for t a k i n g air samples r a p i d l y t h r o u g h o u t t h e p l a n t . LABORATORY OF THE W&l. J. LEMP BREWINGCOMPANY ST. LOUIS .
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AN ETHER RECOVERY TUBE By J. M. PICKEL Received December 19, 1914
I n f a t extractions with t h e K n o r r flask, i t i s . c u s t o m a r y t o recover t h e e t h e r b y removing t h e extraction t u b e a n d p u t t i n g i n its place a t e s t t u b e . T h e accompanying sketch shows a n a r r a n g e m e n t h y which t h i s exchange of t u b e s a n d a t t e n d a n t loss of t i m e a n d e t h e r are obviated. D u r i n g t h e extraction t h e e t h e r d r o p s f r o m t h e point C i n t o t h e f u n n e l d , which conveys i t i n t o t h e extraction t u b e B. When t h e extraction is finished, t h e o t h e r side of t h e t u b e A is brought under t h e point C ; t h i s is E accomplished w i t h o u t i n t e r r u p t i n g t h e distillation, b y merely t u r n i n g t h e K n o r r flask. T h e funnel, which A is made of either glass or m e t a l , h a s t h e peculiarity of being a half funnel, covering b u t one-half t h e m o i t h of t h e t u b e A t o which i t is fused a t its lower e n d only. T h e extraction t u b e B need n o t /e be over 4 or j c m . long t o accommod a t e a n ordinary charge ( 2 g. s u b B stance) a n d i n s t e a d of t w o holes near its t o p f o r t h e circulation of v a p o r , t w o V-shaped notches filed i n i t s edge are equally efficient. The inside diameter of t h e s t a n d a r d /&e cylinder E is a b o u t 3.2 c m . ( 1 . 2 5 i n c h e s ) ; t h e outside diameter of -4 should therefore he n o t less t h a n 2 . 7 c m . ( 1 ~ / 8 inches). T h e l e n g t h of A should be t h e greatest possible witho u t touching t h e point C when i t is revolved. T h e inside diameter of t h e necks of t h e K n o r r flasks need n o t , a n d should n o t , be less t h a n 2 2 or 2 3 m m . I n t h a t case, t h e ext r a c t i o n t u b e can be dispensed with, a n d i n its stead a standard paper thimble, 19 m m . diameter, used. T h e t h i m b l e is placed inside t h e neck of t h e K n o r r , i t s lower e n d reaching down t o within I cm. of t h e surface of t h e e t h e r ; i t m a y be conveniently s u p p o r t e d i n t h a t position b y a small copper wire perm a n e n t l y wound a r o u n d i t , e n d s of t h e wire on opposite sides resting on t o p of t h e neck of t h e K n o r r . T h e space gained i n t h e cylinder E b y t h u s sinking t h e extraction t h i m b l e i n t o t h e K n o r r , makes i t possible t o give a d d e d l e n g t h a n d capacity t o t h e recovery t u b e A . Moreover, t h e extraction t a k e s place i n e t h e r
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vapor, a t practically t h e boiling point of e t h e r , a n d i t is claimed t h a t a n extraction i n t h a t case is complete in a b o u t 4 h o u r s instead of t h e usual sixteen. NORTH CAROLINA DEPARTMENT OF AGRICULTURE RALEIGH
______ A CONVENIENT FORM OF WEIGHING PIPETTE By A. T. MERTES Received January 27, 1915
For conveniently a n d accurately weighing o u t quantities of glycerine such as a r e used i n t h e determination of glycerol b y t h e acetine method, t h e writer devised t h e f o r m of a p p a r a t u s shown. It is convenient a n d useful for weighing o u t oils for t h e determination of t h e Iodine N u m b e r . especially those oils having a high iodine absorption, a n d which require a n accurate weight. For Koettstorfer a n d Reichert-Meissl Numbers, t h e p i p e t t e m a y b e calibrated so a s t o assist i n delivery of t h e proper a m o u n t of f a t or oil. T h e p i p e t t e c a n be m a d e b y a n y one having a little skill i n glass working. T h e writer uses a n old I O cc. p i p e t t e a n d fuses a glass stopcock t o one end. T h e o t h e r e n d of t h e b u l b is draivn o u t a n d b e n t i n t o a hook a s shown i n t h e sketch. I n order t o fill t h e pipette, a r u b b e r t u b e is a t t a c h e d t o t h e u p p e r e n d a n d t h e desired a m o u n t of t h e f a t or o t h e r substance sucked u p i n t o i t . T h e stopcock is t h e n closed, t h e delivery t u b e wiped off a n d t h e p i p e t t e suspended b y t h e hook f r o m a balance a n d weighed. 6537 WOODLAWK AVEXUE,CHICAGO
A FILTER-PIPETTE FOR ETHER B y J. 34. PICKEL
Received December 17, 1914
T h e accompanying illustration shows a device for filtering e t h e r without waste a n d simultaneously de-
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livering it i n requisite measure i n t o f a t extraction flasks.
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The e t h e r is forced by the r u b b e r bulb G , through t h e filter C, u p t h e t u b e E, into t h e p i p e t t e B, which delivers it i n t o t h e flasks. T h e b u l b has only one valve; t h e small hole H i n its side is t o be closed by t h e t h u m b d u r i n g compression a n d t o be uncovered t h e instant t h e e t h e r begins t o overflow i n t o the t u b e i. T h e filter i s a n o r d i n a r y p a p e r t h i m b l e for fat extraction, fitting s n u g and t i g h t over t h e tube D, which is a t t a c h e d by fusion or by cork t o t h e tube E. A t h i m b l e 19 mm. in diameter and extending 2 or 3 c m . below the e n d of t h e t u b e D furnishes a m p l e filtering surface. A few wrappings of t h r e a d will m a k e it fast t o D. T h e p i p e t t e is what is k n o w n siphon. It consists of t h e cylinder a b o u t 2 7 m m . a n d length I O or 1 5 quired; t h e fused-in tube i, a b o u t
as t h e engineers’ B, inside diameter cm., as m a y b e re3 or 4 mm. inside
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diameter and about 57 mm. long above its union with t h e cylinder; t h e c a p j , about 8 m m . inside d i a m e t e r b y a b o u t 53 m m . long; t h e v e n t t u b e f. A p i p e t t e of these dimensions will deliver a b o u t 2 5 cc., ample i n t h e Raleigh climate for an o r d i n a r y extraction ( 2 g. of s u b s t a n c e ) , b u t i t is well t o give the p i p e t t e g r e a t e r capacity t h a n t h a t a n d reduce it t o a n y desired volume by placing inside the cylinder glass beads, or b e t t e r , glass rods. T h e c a p j is s u p p o r t e d on t h e e n d of i, which e n d should b e g r o u n d slanting o n opposite sides, V-shaped, permitting the p,zssage of t h e liquid. This method of filtering e t h e r was devised a n d used by t h e writer six or eight years a g o b u t it h a d fallen into disuse until t h e past winter since which time he h a s again h a d occasion t o m a k e n u m e r o u s fat extractions. NORTHCAROLINA DEPARTMENT OF AGRICULTURE RALEIGH
ADDRESSES THE DYESTUFF SITUATION AND ITS LESSON’ B y ARTHURD. LITTLE
Manufacturers of American flags are in no immediate danger of having to rely upon Cape Cod cranberries for their red or California skies for their blue. Nor is i t probable that our textile manufacturers generally will be forced to adopt the suggestion that we utilize our native rainbows to supply the tinctorial requirements of their industry. Six months ago the situation was different. You could have sold rainbows by the foot. The people generally and even the consumers of dyestuffs awoke a t the first declaration of war to the long patent fact that the industries of these United States are dependent upon Germany for their supplies of coloring matters, synthetic drugs and many other highly necessary products derived from coal tar. A situation which had been eminently satisfactory to consumers for many years suddenly appeared humiliating and intolerable when the embargo first threatened to cut off supplies. There were insistent demands for the immediate inauguration of an American coal-tar color industry to relieve the situation and render impossible its recurrence. It was to be established by changing the tariff and the patent laws and letting somebody else find the money. Government ownership of dyestuff plants was not considered seriously because there were no German plants interned. With the lifting of the embargo and the resumption of shipments by way of Rotterdam most of the humiliation disappeared while now there is even a growing disinclination upon the part of textile manufacturers to let the other fellow find the moneyand make those essential changes in the tariff. The situation nevertheless remains one to cause concern and involves many factors which are worthy of your serious consideration. All the world knows that during the last fifty years a sweeping revolution has been effected in the art of dyeing. The vegetable dyes like logwood, fustic, sumac, madder, indigo and many others, the few animal dyes like cochineal and the relatively crude mineral pigments have all been displaced completely or in greater part by the products of synthetic chemistry after a record of tinctorial service extending back to the days of Genesis. The coal-tar color industry, which began in 1856 with the discovery of mauve by an English boy of eighteen, known later as Sir William Henry Perkin, soon took root in Germany where it has attained its present great development and delicately adjusted organization mainly through the genius of a few and the plodding 1 Address before the United States Chamber of Commerce, Washington, February 5 , 1915.
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industry of many German chemists, the far-sighted courage of German financiers and the technical and business sagacity of German managers. It is in a very real sense a created industry brought into being by the reaction of intellect upon the black chaos of coal tar. It is peculiarly a German industry and its products for the most part may justly and proudly bear the legend, “Made in Germany.” Contrary to popular belief the products of this industry have displaced the old vegetable dyes because Ihey are better, brighter, faster, easier of application, cheaper and incomparably wider in color range. With our textile and paper mills, paint and varnish manufacturers, makers of printing inks, and many minor industries thus definitely committed to the use of coal-tar dyes it is not surprising that the sudden prospect of a dyestuff famine should have occasioned grave concern. At the outbreak of the war the textile mills were generally credited with having not more than five months’ supply on hand. The other industries concerned were probably less fortunate. For a time t h e German embargo on dyestuffs prevented shipments, and stocks were rapidly deple$ed. Through the persistent, earnest and capable efforts of American representatives of the German manufacturers shipments have been resumed under some restrictions but with reasonable regularity. The German plants are running a t about 60 per cent capacity and distribution of their product is regulated by the government through the Society of Dyestuff Manufacturers. The basis of allotment is said to be 75 per cent of the 1913 consumption distributed over monthly shipments which must go forward in American boats. There is little doubt that to prevent reshipment to the allies it is the German policy to keep our own mills in a chronic state of dyestuff hunger. As a result many mills are now running from hand to mouth, others claim to be provided for three months and a few for a somewhat longer period on certain lines of colors. As a result of the close interdependence of the coal-tar dyes and coal-tar explosives industries there has been a practically complete cessation of receipts of such dyes and developers as require for their manufacture nitric acid or raw materials derived from coal tar and available for the production of explosives. Such materials for example are toluol and carbolic acid. The acid blues and acid blacks largely used in dyeing woolens are already scarce as are also most yellows and oranges and a wide variety of blues and greens. Paranitraniline, used in connection with pigment red in poster work, is practically out of
