The Chemistry of Pine Oil - Industrial & Engineering Chemistry (ACS

DOI: 10.1021/ie50069a005. Publication Date: September 1914. ACS Legacy Archive. Cite this:Ind. Eng. Chem. 1914, 6, 9, 720-723. Note: In lieu of an abs...
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bleaching operations be conducted in solutions. T h e piling of t h e goods, either saturated with chemick or s a t u r a t e d with acid, cannot be as efficient a s allowing t h e goods t o lie in solutions. A simple test t o determine whether t h e bleached fabric is permanent in color consists in steaming t h e cloth for one hour a t a pressure of 5 pounds per square inch. If t h e color be permanent there is no change in shade, or yellowing, as it is t e r m e d ; b u t if t h e bleaching b e n o t welldoneorthorough, t h e whiteturnsyellowish. T h e change of shade toward yellow, or toward the originalcolor, serves as a n index of t h e quality of t h e bleach. F A I L U R E O F W E T T I N G O U T TEST

T h e six samples analyzed, when tested b y t h e wettingo u t method described above t o determine t h e efficiency of t h e boil, a n d b y t h e steaming method t o determine t h e permanence of t h e bleached goods, give t h e following results: T h e gray goods a n d t h e sample t a k e n from t h e steep did not sink in water, while all t h e other samples sank instantly. No difference in t h e time required for t h e pieces t o reach t h e bottom of t h e beaker could be noted in t h e pieces t a k e n from t h e second boil, t h e chemick or t h e sour. The piece, however, t a k e n from t h e first boil required a perceptibly longer time t o reach t h e bottom. N o better illustration could be given of t h e failure of tests of this character t o give positive knowledge. There is, in t h e sample taken from t h e first boil, 79.6 per cent of t h e t o t a l fats a n d waxes, a n d in t h e sample t a k e n from t h e second boil 36 per cent, or a difference of 43.6 per cent; yet t h e wetting o u t tests show no corresponding difference. B u t we must, however, note t h a t t h e sample t a k e n from t h e first boil showed t h a t 91.7 per cent of t h e proteins are eliminated. We must al‘so note t h a t , after t h e removal of t h e proteins, more t h a n twice as much of t h e f a t s a n d waxes are eliminated by one boil a s are removed b y t h e steep a n d t h e first boil. This raises t h e question, do t h e colloidal proteins serve a s a more efficient waterproofing t h a n t h e f a t s a n d waxes? When steamed, of t h e samples not bleached, t h e sample from t h e gray a n d t h e sample from t h e steep showed t h e sameyellowing, becoming decidedly browner. T h e samples from t h e first a n d second boil showed t h e same slight yellowing, a n d t h e samples from thechemickand t h e sour hardlychanged in tone or shade. CONCLUSION

F r o m these results we must conclude t h a t t h e proteins are t h e cause of t h e yellowing of cloth in steaming, rather t h a n t h e f a t s a n d waxes. Until we have positive proof t h a t t h e amounts of t h e pectin substances present are t h e cause of yellowing in steaming, I think t h e above statement is a safe inference from t h e analytical results. This investigation has been made in a n effort t o determine what constitutes a good bleach from a chemical standpoint. It appears from t h e results t h a t such a definition is possible. It now remains t o compare, b y t h e sarrie methods, goods not well bleached with those t h a t are well bleached, a n d t h u s determine t h e definite factors. PROVIDENCE,R. I.

Vol. 6 , N o . 9

THE CHEMISTRY OF PINE O n 1 B y MAXIMILIANTOCH

One of t h e industries, which has developed as a result of t h e policy of conservation in t h e United States, is t h e manufacture of useful products from resinous woods. Enormous quantities of t h e latter, which in previous years were considered of little or no use a n d were deliberately burned in huge burners, especially constructed for t h e purpose, or were simply allowed t o go t o waste, .are now being economically a n d profitably manipulated for t h e recovery of turpentine, pine oil, a n d rosin, or t h e production of t a r oils, pine pitch a n d charcoal. T h e two commercially important methods in vogue are, ( I ) t h e steam a n d solvent or extraction process a n d (2) t h e destructive distillation process. Mr. H. T. Yaryan has taken out letters p a t e n t on a process for extracting turpentine a n d rosin from resinous woods, which very well illustrates t h e extraction method as practiced today. Resinous wood, reduced t o fine chips by passing through a wood chipper, is charged into a n iron vessel through a charging door a t the top. The wood rests upon a false bottom over a coil supplied with superheated steam for producing a n d maintaining t h e proper temperature within t h e iron chamber. T h e door a t t h e t o p a n d t h e discharge door a t t h e bottom are closed, a n d t h e current of superheated steam is driven i n t o t h e mass of chips. This is continued until t h e more volatile turpentine has been vaporized a n d driven over i n t o t h e condensers. T h e wood in t h e extraction vessel is left charged with a small percentage of heavy turpentine, together with pine oil a n d rosin. Steam is s h u t off, t h e excess moisture in t h e hot wood is removed by connecting t h e vessel with a vacuum p u m p , a n d finally, a liquid hydrocarbon (b. p. 24c-270~ F . ) is sprayed over t h e t o p a n d allowed t o percolate down through t h e pores of t h e wood. T h e resinous materials are t h u s thoroughly a n d completely extracted, a n d passed into a storage t a n k , from which t h e y are pumped i n t o a still used for separating t h e component parts of t h e solution. From t h e still t h e hydrocarbon solvent is readily separated from t h e heavier pine oils by distillation under reduced pressure, on account of t h e great difference in t h e boiling point between t h e pine oils a n d t h e hydrocarbon solvent, t h e former boiling between 3 jo-370’ F. The pine oils are in t u r n separated from’ t h e rosin b y distillation with superheated steam. This process has been operated on a n enormous scale by t h e Yaryan Naval Stores Company,2 with plants a t Brunswick, Ga., a n d Gulfort, Miss. This Company’s Brunswick, Ga., plant alone utilizes from 500-600 tons of wood each 24 hours-probably a larger consumption t h a n t h e combined pine wood destructive distillation plants of t h e country. Other so-called “low temperature” processes deserve mention as possessing features of merit, although t o 1 Presented before t h e New York Section of the Society of Chemical I n d u s t r y , T h e Chemists’ Club, April 24, 1914. 2 T h e followine is a list of t h e Yarvan U. S. patents: 934,257, September 14, 1609 No. 915,400, March 16, 1909 964,728, July 19, 1910 915,401, March 16, 1909 992,325. M a y 16, 1911 915,402, March 16, 1909 922,369, M a y 18. 1909

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d a t e sufficient d a t a d o not appear t o be available to shon. their t r u e value when operated on a large commercial scale. T h e Hough process, for example, is t o be considered essentially a preliminary t r e a t m e n t i n t h e manufacture of paper pulp from resinous woods. Chipped wood is placed in a retort a n d subjected t o t h e action of a dilute alkali. T h e rosins are saponified a n d t h e soap separated from t h e alkaline liquor b y cooling a n d increasing t h e alkali concentration t o t h e desired degree. T h e rosin soap m a y be sold as such, or treated with acids for recovery of t h e rosin. T h e turpentine a n d pine oils are recovered either b y preliminary t r e a t m e n t with s t e a m or during t h e early stages of t h e cooking process. It will be noted t h a t in t h e low temperature processes t h e only products recovered a r e turpentines, pine oils a n d rosins, t h e first two removed through t h e action of steam, either s a t u r a t e d or superheated, a n d

t h e latter through extraction b y use of a neutral volatile solvent or a saponifying agent. T h e so-called “spent wood” m a y be used either for t h e manufacture of paper pulp or as a fuel t o generate t h e power necessary t o carry out t h e process. I n t h e destructive distillation process, t h e wood, in t h e form of cortlwood 4’ t o 6‘ i n length a n d 4 ” t o 8 ” in diameter. is placed in a horizontal retort a n d t h e temperature gradually raised until t h e wood is thoroughly carbonized. T h e factor of greatest importance in t h e successful operation of this process is temperat u r e control, as i t is essential t h a t t h e turpentine a n d pine oils be removed in so far as is possible before t h e temperature at which t h e resins a n d wood fiber begin to decompose is reached. T h e t o t a l volume of distillate as well as t h e percentage volume of each of t h e several fractions 1 hereof, is largely dependent on t h e degree of temperature control. Destructive distillation of resinous wood was first carried o u t in earthen trenches, t h e combustion being controlled b y partially covering t h e wood with earth. T a r a n d charcoal were t h e only products recovered. T h e n came t h e beehive oven, operated i n much t h e same crude manner, b u t recovering t h e more volatile

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distillates, i n addition t o t a r a n d charcoal. This was i n t u r n superseded b y t h e horizontal retort, externally heated, hot gases being circulated either through a n outer shell or through pipes within t h e retort. Next came t h e b a t h process, wherein the cordwood was immersed in a b a t h of hot pitch or rosin, thereby volatilizing t h e turpentine a n d lighter pine oils a n d dissolving t h e heavier oils a n d rosins. After this preliminary t r e a t m e n t t h e b a t h was withdrawn a n d t h e wood s u bj e ct e d t o straight destructive distill a t i on. More recently1 a retort has been devised utilizing t h e basic principle of t h e laboratory oil b a t h . T h e retort is heated b y means of a layer of hot petroleum oil which is k e p t continually circulating between t h e retorts a n d a n outer cylindrical shell t h a t completely surrounds t h e retort proper. I n this way i t is claimed t h e temperature of distillation can be accurately controlled. T h e turpentine a n d pine oil obtained are fractionated a n d rectified b y subsequent steam distillation. I n running t h e retort t h e temperature of t h e oil b a t h is so regulated t h a t t h e heat inside does not exceed 4 j o o F., before all t h e turpentine a n d pine oil have been distilled. T h e products of destructive distillation by t h e several processes are in each case of very much t h e same general nature, namely-turpentine, pine oils, t a r oils, pine t a r , pitch a n d charcoal. I n some instances low grade rosin oils are also produced. “Light Wood” does not refer t o woody fiber which has a light specific gravity. T h e name originated from t h e fact t h a t this particular wood is so rich in oil a n d resinous material t h a t i t is readily used for lighting fires. I n t h e southern portion of t h e United States little bundles of “light wood” are for sale in strips about 1/4 in. in diameter a n d I f t . long. When a fire is applied t o one of these strips of wood i t becomes useful for lighting fires: hence t h e name “light vi-ood.” I have seen “light wood” so rich in rosins a n d oily material t h a t b y transmitted light a t h i n section looked like translucent r u b y glass. It is this particular wood which is most used for t h e distillation of wood t u r pentine, pine oil a n d rosin. The product from t h a t t y p e of pine tree from which turpentine is obtained has always been regarded as producing two materials when t h e sap has been collected a n d distilled. T h e one material is turpentine, a n d t h e other rosin. About t e n years ago, when destructive a n d steam distillation of pine wood became a practical industry, a third substance was recovered. This material, intermediate between turpentine a n d rosin, is now known as “Pine Oil.” As far as I know, no one has yet determined t h e chemical constitution of this intermediate product of t h e pine tree, which has been designated as “Pine Oil.” T w o years ago I started this investigation, which is practically finished, a n d i t is m y privilege t o show you to-night t h e raw material from which pine oil is made a n d t h e various processes by which i t is refined. T h e chemical composition of this material a n d t h e work which led t o its determination will be published, a n d therefore I shall not dwell a t a n y great length on this 1

T. W. Pritchard, THISJOURNAL, 4

(1912), 338.

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phase of t h e subject. There is as yet no s t a n d a r d of purity for pine oil, b u t t h a t it has a definite chemical composition is now fairly well established. T h e only original investigation of t h e chemical composition of pine oil was carried o u t by Dr. J. E. Teeple’ on “Long Leaf Pine Oil.” Dr. Teeple says: “ T h e commercial long leaf oil, as i t comes o n t h e market, is either clear a n d water white, containing 3 or 4 per cent of dissolved water, of it may have a very faint yellow color a n d be free from dissolved water. T h e specific gravity ranges from 0.935 t o 0.947, depending on freedom from lower boiling terpenes. A good commercial product will begin distilling a t a b o u t 206’ t o 210’; 7 5 per cent of a n d jo per i t will distil between t h e limits 2 1 1 ’ - 2 1 8 ’ A sample having a cent of i t between 213-217’. density of 0.945 a t 15.5’ showed a specific rotation of a n d a n index of refraction of a b o u t [a]2gO0-II’, TZ 1.4830. I n fractional distillation of t h e oil t h e specific gravity of t h e various distillates rises regularly with increasing temperature, becoming steady a t about 0.947 a t 217’. “If t h e oil consists essentially of terpineol, CloHlsO, i t should be easy t o convert it into terpin hydrate, C10H2002HzO, b y t h e method of Tiemann, a n d Schmidt.2 T h e conversion was found t o proceed easily when t h e oil was treated with 5 per cent sulfuric acid,

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t h e t r u n k , stumps a n d roots bf t h e same tree have been allowed t o remain on t h e ground for a number of years a n d are t h e n steam distilled, there is obtained, in addition t o t h e turpentine a n d rosin, certain heavier oils formed by hydrolysis a n d oxidation a s a result of exposure t o t h e atmosphere. T o t h e heavier oils t h u s formed a n d yielded u p in t h e process of steam distillation t h e t e r m “pine oil” is properly applied. Pure pine oil has a very pleasant odor, a n aromatic odor similar a t times t o t h e oil of caraway seed or t h e oil of juniper seed. When pine oil is impure it is very difficult t o use it for interior work on account of pernicious odor of .empyreumatic compounds. I t has been used t o a considerable extent for making paints which should d r y without a gloss, a n d as a “flatting” material i t has been very successful. It has t h e excellent quality of flowing o u t well under t h e brush a n d of not showing brush marks, t h e l a t t e r because i t evaporates so very slowly. It is a very powerful solvent, a n d many of t h e acid resins which have a tendency t o separate when t h e y are insufficiently cooked with drying oils will remain together when pine oil is added. Pine oil can be used t o a considerable extent as a diluent in nitrocellulose solutions, a n d a s a cooling agent for t h e reduction of varnishes it also has excellent qualities. T h e author t a k e s this opport u n i t y of stating t h a t o n previous occasions his recomEVAPORATION TESTS

TABLE I-ANALYSES OF PIN= OILS

S-14’499

Sp. gr. at 151/ao C. 0.9423 0.9427 0.9338 0.9330

S-14.501 5.14,560 5-14.561 S-14.562

0.9355 0.9382 0.9350 0.9383

SamDle S-12,200 5.12.201 5-12.496

S-ii:soo

0;SiGi

Color Faintly yellow N o t quite water white Water white Straw color F i l e amber Straw color Water white Straw color Water white

Acid value 0.68 0.29 0.51 0.59 0.49 0.70 0.17 0.73 0.27

Vol. 6, No. 9

Iodine Flash(a) I value point O F C 142.5 170 18.1 118.4 175 17.9 125.4 145 77.0 161 5 160 81.8 173.9 148 80.9 143.2 168 79.0 129.8 175 78.4 160 79.6 142.7 176 78.3 124.4

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ULTIMATE On steam bath ( b ) At room temperature - 65’ F. ANALYSES Per cent loss Per cent loss after after H 0 9 hrs. 2 hrs. 4 hrs. 6 hrs. 8 hrs. 24 hrs. 32 hrs. 11.5 10.4 93.4 27.8 43.8 52.2 67.2 96.7 96.7 11.4 10.7 96.3 20.3 31.8 41.8 50.8 92.4 92.7 11.1 11.9 97.3 30.4 46.9 58.6 70.0 97.5 97.5 10 6 7.6 93.8 10.6 8.5 85.7 11.4 9.6 92.7 3b18 56:6 69:8 80:4 95:5 95:s 11.2 10.4 98.6 39.5 58.9 70.5 82.5 96.5 96.5 11.5 8.9 95.1 46.4 68.0 81.0 88.7 94.0 94.0 11.1 10.6 98.7 24.6 35.3 46.0 53.2 88.8 90.4

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79.0 11.2 9.8 ( a ) Open cup (Tagliabue tester). ( b ) After evaporation a small, hard residue, similar in appearance to pale rosin was left. I n the case of 5-14,999 and 5-14.500, the residue was very dark, almost black in color, due probably to impurities in the pine oils.

either with or without admixture with benzine. If agitated continuously, t h e reaction is complete within 3 or 4 days. If, on t h e other h a n d , t h e mixture is allowed t o s t a n d quietly, t h e formation of terpin h y d r a t e extends over several months a n d produces most beautiful large crystals, which, without recrystallizing, melt a t I I 7-1 18’. When recrystallized from Yield, about 60 per e t h y l acetate t h e y melt a t 118’. cent of t h e theoretical. This forms such a simple, cheap a n d convenient method of making terpin hydrate t h a t i t will doubtless supersede t h e usual manufacture from turpentine, alcohol a n d nitric acid, a n d instead of terpin hydrate serving as raw material for t h e manufacture of terpineol, as heretofore, t h e reverse will be t h e case.” “Pine oil,” as now understood, is t h e heavy oil obtained from t h e fractionation of crude steam distilled wood turpentine. When t h e sap of t h e pine tree is subjected t o distillation in a current of steam t h e volatile liquid-turpentine-consists almost entirely of t h e hydrocarbon, pinene, CIOH16. When, however, 1 2

J . A m . Chem. SOC.,30, p. 412. Bey.. as, p. 1781.

mendations concerning new a n d useful materials for t h e paint a n d varnish industry have been misunderstood in some instances, a n d i t is t o be hoped t h a t this treatise will not be misinterpreted. Pine oil is a new a n d useful material, b u t i t is b y no means a substitute for linseed oil or turpentine or a n y of t h e other materials now on t h e market. It has properties peculiar t o itself, a n d when intelligently used is of considerable value. Practically all of t h e pine oil obtainable contains a small percentage of water in solution, t o which i t clings rather tenaciously, a n d it is by no means a simple m a t t e r t o dehydrate this material. A rather complex apparatus for dehydrating t h e material is necessary with temperature control, b u t t h e test which t h e author has devised for t h e determination of water is q u i t e simple. If 5 cc. of pine oil are mixed with I cc. of a neutral mineral oil, like benzine, kerosene or benzol, a n d a perfectly clear solution is obtained on shaking, no water is present; b u t if there is a n y water present in t h e pine oil t h e water appears a s a colloid, a n d a milky solution is obtained which does not separate after long standing. The fact t h a t pine oil will t a k e

Sept.. 1914

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u p a considerable q u a n t i t y of water a n d still remain clear makes i t useful for emulsion paints such as are very much in: vogue at t h e present time for t h e interior of buildings, a n d i t has been suggested t h a t t h e addition of water up t o j per cent for such a purpose is beneficial on new walls. T h e United States Bureau of Chemistry’ has developed a method for t h e determination of moisture b y t h e use of calcium carbide; TABLE11--ULTIMATE ANALYSES C H 0 1 1 ,i i 10.38 a-Terpineol (theoretical). . . . . . . . . . . . 77.85 11.9 ... French turp. (a).. . . . . . . . . . . . . . . . . . . 87.7 12.1 ... American turp.(a) . . . . . . . . . . . . . . . . . . 87. i 85.7 12.1 2.2 Wood turp.(a) . . . . . . . . . . . . . . . . . . . . . 11.8 3.9 Pine oil-first r u n n i n g . . . . . . . . . . . . . . 8 4 . 3 Distillate-pine oil, 345-380’ F., 17482.6 11.4 6.0 195’C . . . . . . . . . . . . . . . . . . . . . . . . . . (a)hl. Tach, “ T h e Chemistry a n d Technology of Mixed Paints,” b y D. Van S o s t r a n d Company, publishers, New York. ~~

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a t t e m p t e d t o cope with t h e fire problem b y passing laws compelling either t h e “lopping” or burning of t h e tops. T h e Forest Service in leasing timber rights stipulates t h a t t h e tops must be burned or lopped a n d scattered. If only sufficient oil could be obtained t o p a y for t h e cost of handling t h e material, there would be a n economic gain t o t h e lumberman, since lopping or burning entails a n expense with no return whatever for t h e labor involved. This investigation was undertaken with a view t o determining t h e yield a n d composition of t h e leaf oils of t h e more i m p o r t a n t conifers with a view t o their utilization.

Several western species were distilled by hIr. G. LI. H u n t of t h e Forest Service. T h e yields obtained for this is being investigated a t our laboratories, b u t on these oils a n d their composition will be published later. account of being a gas-volumetric method i t is not I n most cases t h e yields from t h e western species were quite feasible for general use in technical laboratories. low. T h e odor of t h e oils from both t h e western a n d h number of commercial samples of pine oil were southern species was peculiar a n d less pleasant t h a n t h e dehydrated a n d analyzed. Tables I , I 1 a n d I11 spruce oil of commerce. This m a y be accounted for indicate t h e results obtained. b y their low alcohol a n d ester content compared with TABLE111-FRACTIONAL DISTILLATION OF COMMERCIAL PINEOIL spruce oil. From t h e yields of oil obtained from t h e Temperature Fraction in 7 15.5’ C . .’ . gr., .” _ T o t a l distillate SD. ’ southern a n d western species i t was thought t h a t a n 2 Water, 100’ 2 7 o:aa2 174-194 5 ’ approximate idea of t h e probable yield of a species 18 0.920 194-205’ 11 n.....933 205-208 i n. . _2u_ could be obtained from t h e cross section of t h e needles. . 208-210 25 53 0.939 T h e inference is logical tHat t h e yield should depend 210-213 35 88 0.941 2 13-2 16 6 94 0,942 on t h e number a n d size of t h e resin ducts per unit of 1 2 16-2 18 95 0.942 2184 99 ... cross sectional area. Cross sections of t h e needles of T h e a u t h o r is glad t o acknowledge here t h e as- several species were made a n d t h e above inference was sistance which was given him b y Mr. C. A. Lunn in verified in a striking manner, as will be noted b y reference t o Figs. I , 2 , a n d 3. furnishing t h e samples of raw materials. 320 F’IFTH.4VE., N S W YORK

OILS OF THE CONIFERAE. I-THE LEAF AND TWIG OILS O F CUBAN AND LONGLEAF PINES AND THE CONE OIL OF LONGLEAF PINE B y A. W. SCHORCER Received July 6, 1914

T h e annual consumption of leaf oils of certain native conifers a m o u n t s t o a b o u t $50,000. T h e principal species distilled for oil are t h e black spruce ( P i c e a mariavta, Mill.), white spruce ( P i c e e c a n a d m u i s , Mill.), hemlock (Tsuga c a n a d e n s i s , Linn.), red juniper ( J u n i p e r u s v i r g i n i u m , Linn.), a n d arborvitae ( T h u j a occid e n t a l i s , Linn.). N o a t t e m p t appears t o have been made t o distinguish between t h e t w o spruce oils a n d it is doubtful if much genuine hemlock oil is t o be found on t h e market, since t h e oils of t h e three species are quite similar a n d for practical purposes no distinction seems necessary. Fritzsche Brothers of hTew York City estimate t h e annual consumption of spruce oil a t .+o,ooc-~o,ooo pounds. I t is extensively employed as a perfume in greases a n d shoe-blackings a n d is quoted a t $0.4j-$0.60 per pound. T h e leaf oil of t h e red juniper is sold a t about t h e same price as spruce oil. a n d is largely used in insecticides. The annual consumption is I j , 0 0 c ~ 2 0 , 0 0 0pounds. T h e annual c u t of lumber from conifers far exceeds t h a t of t h e hardwoods. T h e tops are left i n t h e woods a n d , in addition t o being a total loss, are t h e most fruitful source of forest fires. Several states have :

U. S. Dept. Agric., Bur. Chem.. Circ. 97.

APPARATUS-The still proper was constructed in three parts (Fig. 4). T h e cylindrical body of t h e still for holding t h e needles was 3 feet 6 inches in height by 2 feet 3 inches in diameter, made of No. 16’B. W. G.’ copper. The ends were flanged out a n d attached t o iron rings inches wide. The covers of t h e still a n d of t h e heating vessel were similarly flanged a n d provided with rings. T h e t o p a n d base were clamped t o t h e cylinder b y 2 1 / 2 inch malleable iron clamps, Asbestos wire t a p e was used i n these make a n d break joints. T h e inner base of t h e cylinder was furnished with lugs upon which rested a frame covered with 2 0 mesh No. 2 j B. W. G. brass wire t o support t h e needles. T o reduce radiation a n d resultant condensation of t h e vapors t h e cylinder was covered with asbestos. T h e heating vessel was 3 feet in diameter b y z feet I inch high a n d constructed of No. 16 B. W. G. copper except t h e b o t t o m , which was No. 11 B. W. G. copper. T h e heating vessel was supplied with a 4l/2 inch funnel provided with a lever handle stop, a n d a l / ? inch water gauge. An 8 foot copper pipe, in two sections, two inches in diameter, connected t h e cover with t h e condenser. T h e latter consisted of 2 0 feet of 1 l / 4 inch copper tubing wound in a coil of 1 ’ 1 2 feet internal diameter. The coil was placed in a galvanized iron t a n k 2 feet in diameter b y 2 l / 2 feet deep. T h e receiver (Fig. j) consisted of a 2 gallon aspirator bottle furnished with a brass siphon. During distillation t h e receiver was 1

Birmingham wire gauge.