A Shaker for the Mechanical Analysis of Soil

Horace C . Porter. chemist, of the Bureau of liines. A SHAKER FOR THE MECHANICAL ANALYSIS OF SOIL. By FREZMAS. \YARD. Recei\.ed October 23, 1913...
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F e b . , 1914

T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y

t h u s o b t a i n e d t o solving practical problems i n t h e t r e a t m e n t of m i n e fires. I n v e s t i g a t i o n s h a v e been m a d e i n o t h e r countries a n d t o s o m e e x t e n t also i n t h i s Country, of t h e gases p r o d u c e d in a c t u a l cases of m i n e fires b o t h before a n d a f t e r sealing off n b u r n i n g a r e a . T h e b u r e a u is now m a k i n g , however, p r o b a b l y t h e first a t t e m p t t o i n -

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t y p e of s h a k e r used b y t h e writer a n d believed t o h a v e certain advantages. DESCRIPT1Ox.-The principle is as follows: T h e b o t t l e s with soil a n d w a t e r a r e e n d e d over a n d over, t h u s allowing t h e c o n t e n t s t o fall f r o m one e n d of t h e b o t t l e t o t h e o t h e r . T h i s is accomplished b y h a v i n g t h e b o t t l e s a t t a c h e d radially t o a wheel which is r o t a t e d slowly i n a vertical plane. T h e m a c h i n e used b y t h e writer is “ h o m e - m a d e ” a n d consists of t w o small c a r t wheels sixteen inches in d i a m e t e r , b o t h o n t h e s a m e axle a n d t o u c h i n g h u b t o h u b : t h i s leaves t h e edges of t h e t i r e s a b o u t t h r e e inches a p a r t . S t r i p s of t i n fastened t o t h e fellies serve n o t only t o hold t h e t w o wheels t o g e t h e r , b u t also with t h e fellies a c t as a b r o a d groove ( I ~ / zinches wide) for a belt t o r u n on. T h e b o t t l e s used a r e t h e kind k n o w n commercially a s “ f o u r ounce s a m p l e oil bottles:” t h e y a r e a b o u t six inches long a n d one a n d one-half inches in d i a m e t e r , a n d a r e f i t t e d with r u b b e r s t o p p e r s : t h e y h a v e a c a p a c i t y of 1 2 0 cc. T h e base of each is slipped i n t o a sleeve of t i n f a s t e n e d n e a r t h e h u b : a mire c l a m p secures t h e b o t t l e a t t h e neck. T h e wheel t h u s c o n s t r u c t e d will hold sixteen of t h e s e b o t t l e s a r r a n g e d radially-eight on a side. I t m a y b e a t t a c h e d t o a m o t o r b y m e a n s of a b e l t . P l a t e I is a p h o t o g r a p h of t h e machine.

“COMBCSTIOS

OF COAL”

.kPPARATUS S H O W I N G G A S A N D A I R

CONXfiC

T I O N S TO C O X B C S T I O i Y C I I A X B E R

v e s t i g a t e such problems in a n e x p e r i m e n t a l a p p a r a t u s which p e r m i t s careful c o n t r o l of conditions a n d y e t is o n a scale nearly c o m m e n s u r a t e v-ith mining o p e r a tions. T h e s e investigations a r e being carried o n b y H o r a c e C . P o r t e r . c h e m i s t , of t h e B u r e a u of l i i n e s . A SHAKER FOR T H E MECHANICAL ANALYSIS O F SOIL By FREZMAS \YARD

Recei\.ed October 2 3 , 1913

IsTRoDvcToRy..-In t h e mechanical analysis of soil o n e of t h e p r i m e requisites is t h e complete s e p a r a t i o n of all t h e particles before s o r t i n g t h e m i n t o groups or g r a d e s according t o size. T h e t e n d e n c y i n t h e n a t u r a l soil is f o r t h e finer particles e i t h e r t o g a t h e r a m o n g themselves as aggregates or t o cling t o t h e larger grains. If a complete s e p a r a t i o n is n o t effected t h e per c e n t of t h e finer grades of soil will be below, a n d t h a t of t h e coarser grades a b o v e t h e t r u t h . T h e s e p a r a t i o n c a n be effected mechanically i n one of t w o ways---pestling a n d s t i r r i n g ; o r s h a k i n g , as a d v o c a t e d b y t h e D e p a r t m e n t of Agriculture*-water ( v e r y slightly a m m o n i a c a l ) being a d d e d i n e i t h e r case. T h e essential i d e a of t h e l a t t e r is t o place b o t t l e s containing soil a n d w a t e r i n a horizontal position in t r a y s which a r e jerked b a c k w a r d a n d f o r w a r d b y m e a n s of a n eccentric a t t a c h m e n t . T h e p u r p o s e of t h i s article is t o describe a different C. C. Fletcher and H. Bryan, “Modification of the Method of Mechanical Soil Analysis,” U. S. Dept. Agr., Bur. Soils, Bull. 84, 1912.

PLATE I

T o operate-put weighed ( I O g r a m s ) s a m p l e of soil i n b o t t l e ; fill one-half full of w a t e r which is slightly a m m o n i a c a l ; a t t a c h b o t t l e t o wheel a n d revolve a t t h e r a t e of t w e n t y - f i v e revolutions a m i n u t e ; l e t r u n for t h r e e hours. ADVAr;TAGEs.-Separation b y stirring a n d pestling is t o o laborious, c o n s u m e s t o o m u c h t i m e , does n o t a l w a y s result i n a clean s e p a r a t i o n a n d h a s a t e n d e n c y t o mechanically f r a c t u r e t h e particles of soil. B o t h t h e s h a k e r m e t h o d s are n o t only safer, a n d more effective, b u t , since t h e y c a n be r u n b y m a c h i n e r y , a r e c o n v e n i e n t . A n d in e i t h e r case t h e r e m o v a l of t h e g r a d e s silt a n d clay b y s e d i m e n t a t i o n a n d d e c a n t a t i o n

T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y can be undertaken directly after the shaking without transferring t h e whole s a m p l e t o a n o t h e r vessel. The w r i t e r believes t h a t h i s m e t h o d is b e t t e r t h a n the one u s e d by t h e B u r e a u of s o i l s i n two respects. In the first p l a c e the machine is s i m p l e and inexpensive. A gre;tter advantage i s t h e s a v i n g of t i m e . C l e a n s e p a r a t i o n s can b e effected i n three h o u r s , and i n s o m e

1 By

E. H. FRENCH AND

JAMES

R . WITHROW

I n treating a subject that has as many phases as this one, i t will be necessary to discuss briefly an allied industry, namely, that of Gum Turpentine as distinguished from Wood Turpentine, in order that the reasons calling for the development of this latter industry may be seen with the proper perspective. That the Wood Turpentine Industry is at present at an extremely low ebb is unquestionably true. hTevertheless, it is likewise true that its scientific develapment is a n economic necessity for certain localities, in order that waste may be conserved, that the products from waste replace those from the fast disappearing pine and fir forests and that cut-over land may be cleared a t a profit instead of a t a loss. Therefore, in this instance, as is often the case, necessity compels development. The fact that thousands of dollars have been expended and lost in the incubation of this industry has been due, in our opinion, to three main causes, any one of which in itself would account for failure: first, the lack of practical scientific engineers experienced in this or analogous fields; second, financing for the sale of stock and securities rather than product; and third, lack of efficient marketing organization. It must also be borne in mind, that owing to the number of different processes, there was caused a lack of uniformity of product, which naturally tended to increase selling costs. Except to the U. S. Navy, little, if any, wood turpentine has been sold on thorough specifications. There has as yet been no real attempt by manufacturers to effect a general standard, although a few years ago the producers of the practically defunct steam process turpentine did make an attempt to standardize their product. One of the important influences that tended a t first toward the development of the industry and later proved extremely detrimental, was the speculative nature of the naval stores market. This was made up entirely of gum turpentine and rosin, upon the prices of which the relative wood turpentine values were determined. This market in the past has been subject to violent price changes, a fluctuation of from 30 cents to over $1.00per gallon having been experienced, which was due almost wholly to speculation. Naturally, therefore, during the upward swing of prices an unnatural development occurred, and plants using costly processes and with inefficient management were profitably operated and exploited. It followed, of course, that when the national government, through criminal prosecution, put a stop to excessive speculation, a corresponding reaction occurred, ruining many concerns which required abnormal prices for financial success. Unreasonably high prices not only encouraged the development of the wood turpentine industry, but also caused an expansion in operations by the gum turpentine manufacturers so that a larger percentage of trees, and many very young trees, were boxed, causing overproduction. Presented a t the 6th Annual Meeting of the Amer. Inst. of Chem

Eng., The Chemists’ Club, New York, December 10-13, 1913.

No. 2

cases t w o h o u r s : t h i s is a s a v i n g of at l e a s t f o u r h o u r s o v e r t h e B u r e a u m e t h o d . If the q u a n t i t y of t h e w a t e r u s e d i n t h e b o t t l e s i s r e d u c e d one-half, a clean s e p a r a t i o n result s i n m u c h less than t h r e e h o u r s , b u t t h e r e is a t e n d e n c y for the g r a i n s t o suffer Some a b r a s i o n . SCHooL YALEUNIVERSITY HAVEN,CONN.

SHEFPIELD h’EW

ADDRESSES

THE PRESENT STATUS OF THE WOOD TURPENTINE INDUSTRY’

Vol. 6,

1I G U M TURPENTINE

The method of producing oil of turpentine from the resins of coniferous trees, consists in cutting a broad wedge-shaped notch or cup a t the base of the tree and removing the bark immediately above the notch for about 18 to 24 inches. The resin exuding from the peeled area runs into the cup a t the bottom and is collected from time to time. Each succeeding season the barked area is increased until i t reaches about the height of one’s head, usually taking five or six years. As many as four “boxes” are thus cut on one tree, depending on its size, permitting only enough of the original bark to remain to prevent the death of the tree. After collecting sufficient quantity of the resin, i t is distilled in a copper still, usually a “fire still,” equipped with a live steam jet or a water supply. The turpentine thus produced is not carried farther in any refining process, but is ready for the market. The residue in the still is the rosin of commerce and is barreled a t the still. The dross obtained by filtering sticks, dirt, etc., from the rosin is in many places being-worked into cheaper grades of rosin. With rosin a t an average price, i t is generally figured that to make the operation profitable, about 42 cents per gallon must be obtained for the turpentine. The marketing of the products is done through “factors” as they are called; that is, companies or individuals who contract with the producers for their output, supply them with funds for pay-rolls, etc., and advances when necessary. These “factors ” take the product when produced, but usually have no other connection with the producer. Savannah, Georgia, is the leading naval stores center in the world and usually Savannah prices are accepted as the standard. Jacksonville and Pensacola, Florida, Brunswick, Ga., and New Orleans, La., are also large “factor” centers for this industry. This method of producing turpentine is generally conceded to give the best turpentine and rosin, but unless more scientific methods are very widely adopted the time is rapidly approaching when it will be necessary to supply these products from another source, for present methods of operation are beginning to be looked upon as directly antagonistic t o all ideas of conservation under American lumbering conditions, as they so weaken the trees that the loss from windfalls is extremely large. I n fact, many large lumber companies have given up “boxing” Tor this reason, and also because they feel that the growth of the young tree is retarded. Modifications of the old “boxing” methods are being used in some places. Metal cups are substituted for the box cut in the base of the tree and light chipping is being tried. It is claimed that the loss from windfalls is considerably reduced by some of these modern improvements. At least one large Southern lumber company is a t present experimenting on 5,000 acre units in order to determine definitely, if possible, the merits of these new cups and other modifications as to yield and influence on windfalls, and also to decide the effect “boxing” may have on finished lumber. WOOD TURPENTINE

Wood Turpentine came into commercial notice about the year