M a y , 1915
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 CHEMISTRY
clearly how this change in rate of evaporation takes place. From the consideration of t h e changes taking place in the soil i t is evident t h a t t h e conditions of the soil are not constant. T h e composition as well as t h e physical properties of t h e soil is constantly changing a n d these changes must be considered in a n y study of soil conditions. T h e largest and most important changes in the soil are wrought b y a changing water content. The influence of these changes fo!!ow a definite Iav,. and with this understanding of the influence
of moisture variation, i t remains t o investigate t h e amount of such changes due t o specific soil conditions. S U If MA R Y
T h e engineering properties of t h e soil are t h e properties of interest from t h e physical standpoint and are identical with those physical properties of importance t o agricultural operations. T h e factors influencing t h e physical properties are mechanical composition, mineralogical composition a n d moisture content. All of these are constantly changing, b u t t h e greatest variation occurs in t h e moisture relations of t h e soil. A s t u d y of t h e moisture relations has demonstrated t h e fact t h a t all of t h e physical properties change with a changing moisture content and with a n y given soil there is a particular moisture content iit which t h e properties either reach a maximum or minimum value; this moisture content is t h e critical moisture content of t h e soil. The soil, if allowed t o become wet a n d dry out several times, reaches a condition of compactness known as "natural packing." This compactness varies with t h e moisture content just as t h e other physical properties do. T h e s t u d y of the engineering properties of t h e soil will consider t h e changes due t o specific soil conditions, b u t must recognize t h e dynamic soil conditions. BUREAUOF SOILS U. S DEPARTMENT OF AGRICULTURE, WASHIXGTON
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in a great number of p r i n a r y rocks, granites, syenites and gneisses, by L. Dieulafait,' and in many varieties of marble, calcareous rocks and English chalk b y Kirchoff and Bunsen.? Lithium is also very often found in mineral waters a n d salines, It has been found in the larger bodies of water: in t h e Dead Sea, b y Dieulafait3 and in the waters of t h e llediterranean Sea, Red Sea, Indian Ocean, Chinese Sea, Atlantic Ocean, Antarctic Ocean and t h e S o r t h e r n Ocean b y the same author,' the concentration of lithium being great enough in the wa.ters of the Mediterranean t o make it easy t o detect in the residue from one cubic centimeter of water. Being so n-idely distributed in rocks one would expect t o find lithium in t h e soil and plants supported b y the soil. Beet5 and tobacco plants take u p considerable quantities of this element from t h e soil. Lithium was found in tomatoes, chick peas and Iris germinica by Passerine6 and in a great number of plants growing exclusively in Austria by T ~ c h e r m a k . ~Bunsen and Kirchoff found lithium in t h e ash of t h e wood of trees grown on a .granite soil and in the ash of all kinds of cereals grown in the valley of the Rhine. Lithium has also been found in t h e blood and muscles of m a n a n d ruminant animals by Kirchoff and Bunsen and in nearly all t h e organs of t h e h u m a n body by Herrmann.8 Lithium has been known t o be present in soils, for a long time, b u t there are few quantitative estimates of this element. I t was found present in all soils examined by R o b i n ~ o n . ~ T h e lithium was obtained together with t h e sodium b y t h e J. Lawrence Smith method and t h e excess of platinum used t o precipitate t h e potash removed b y treatment with hydrogen sulfide. T h e lithium and sodium salts remaining in solution are filtered and concentrated t o small volume T h e lithium was determined by means of a Hilger wave length spectroscope using t h e line of 6708.2 wave length. The intensity and duration of the line, compared with t h a t of a standard solution, served t o measure t h e content of lithium. T h e method of comparing t h e spectra of unknown and standard was very similar t o t h a t of Truchot, with t h e use of platinum spiral and addition of sodium chloride t o standards as described b y Skinner and Collins.1o A blank determination showed small amounts of lithium in reagents b u t not enough t o interfere with t h e determination. T o determine whether appreciable amounts of lithium are volatilized during heating twice t o drive off ammonium salts, standards were made b y adding lithium, in amounts occurring in soils, t o powdered quartz. No loss of lithium occurred
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Ann. chim. phys., IS] 16, 377-391. Chem. h'ews. 98, 151-2. Compt. rend., 94, 1352-1354. 4 A n n . chim. phys., [SI 16, 377-391. 6 von Lippmann, Ber., SO (18971, 3037-3039. 6 Sfaz. S p e r . Agrar., 20, 471-476. 7 Z e d . Landw. Versuchs-Wesen. Oeslerr., 2, 56G-572. 1 2
LITHIUM IN SOILS B y L. A. STEINKOENIC Received January 6, 1915
Lithium is very widely. though not abundantly, distributed in nature. I t has been found in a large number of sedimentary rocks examined by -4. Hiker.' 1
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T H E J O U R N A L O F I N D U S T R I A L AlVD EiVGINEERIiVG C H E M I S T R Y
PER CENTLITHIA SOILS .4NALYZED FOR LITHIUM Soil Subsoil SOILSOF RIVXXA N D FLOOD PLAINS PROVINCE ~ ~ ~ Cahaba Fine Sandy Loam, Clay County, G a . . , , . , . , , . 0 , 0 0 2 0 . 0 0 4 Cahaba Very Fine Sandy Loam, Minden, L a . , . . . . . . 0.001 0.002 SOILSOF GLACIAL AND LOESSIAL PROVINCE Memphis Silt Loam, Grenada Co., Miss. . . . . . . 0 . 0 0 2 0.002 Memphis Silt Loam, Smooth Phase, Miss. .............................. 0.002 Carrington Loam, Lawville, Wis. . . . . . . . . . . . . . . . . . . . 0 . 0 0 2 ... Gloucester Stony Loam, 3 mi. E. Marlboro, N. H., ,,. 0.003 ... Volusia Silt Loam, 3 ‘ 1 2 mi. S. W. Naples, N. Y . ... SOILSOF COASTAL PLAINSSERIES Ruston Fine Sandy Loam, Minden, La , . . , . . 0.002 0 . 0 0 3 0.007 Susquehanna Clay, Clark Co., Miss.. . Susquehanna Fine Sandy Loam, Smith Co., Texas.. , . 0 , 0 0 3 0.003 Orangeburg Sand, Terrel Co., G a . . . . . . . . . . . . . . . . . . . . 0 , 0 0 2 0.003 Sorfolk Fine Sandy Loa i. S. W. hfurph quit Co., Ga . . . . . . . . . .............. 0,003 Susquehanna Fin , Colquit Co., Ga 0.003 Portsmouth Fine 0,004 Tifton Fine Sandy Loam, Bellville, G a . . . . . . . . . . . . . . 0 . 0 0 2 0.004 SOILSOF THE LIMESTONEVALLEY A N D UPLAND PROVINCE Hagerstown Loam, 1 mi. N. W. Conshohocken, P a . , . , 0.010 ... SOILS O F GREAT PLAINS P R O V I N C E 0.003 ... Oswego Silt Loam, 2 mi. N. W. Manhattan, Kan Colorado Sands, Greeley, Col . . . . . 0.002 SOILSOF PIEDMONT PLATEAU PROVINCE Louisa Loam, Trevilians. Va.. ...................... 0.003 ~~
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Vol. 7 , NO. j
during t h e analysis of these standards. -4pproxi~ ~ the mately t h~e same a-m o u n t of~ sodium ~chloride as soil samples contained was added t o t h e standards. T h e soils were taken from six different areas. T h e results of t h e analyses are given i n t h e accompanying table. Lithium, although occurring i n small amounts, was found present i n all soils examined and in many cases i n larger amounts t h a n rubidium’ is usually found. T h e content of lithium does not seem t o follow t h a t of a n y other element in t h e soil. Nearly t h e same a m o u n t of lithium is found i n soil a n d subsoil b u t in most cases t h e proportion found in t h e subsoil is greater. BUREAU OF SOILS
u. s. DEPARTMEXT OF AGRICULTURE, WASHINGTON
LABORATORY AND PLANT SAND BLAST FOR MARI(1NG GLASSWARE By GEORGESPITZERA N D L.S.TRACHSEL Received March 19, 1915
Sometime ago i t became necessary for t h e senior writer t o devise a means for marking glassware. The main objects desired were rapidity, economy a n d durability. Where large quantities of glassware are t o be marked rapidity is very essential. The method of using a n emery wheel or emery paper answers t h e purpose quite well where only “spot etching” is required a n d t h e glassware is sufficiently strong t o withs t a n d t h e pressure of t h e rapidly moving emery wheel or emery paper. When lcttering is t o be done other methods are resorted t o , a n d t h e so-called diamond ink or hydrofluoric acid method is sometimes used. Before employing either hydrofluoric acid or diamond ink for effective etching i t is necessary t h a t t h e glassware be warmed a n d free from grease or dirt. T h e rubber s t a m p s used for applying t h e etching agent clog u p with t h e paste, making frequent cleaning necessary a n d also making t h e whole operation very slow a n d sometimes unsatisfactory. I n addition t h e etching done b y t h e hydrofluoric acid is fine-grained a n d soon becomes very faint if t h e glassware is handled t o a n y great extent. This is t r u e when grease or greasy substances come i n contact with t h e etching. T o overcome these difficulties a n effort was made t o devise a sand blast, embodying t h e features’ necessary for rapid work, economy i n various relations a n d one t h a t would give durable markings. I n this we be1iei.e
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we have succeeded, in a great measure, a n d it is hoped t h a t perhaps others who may have occasion t o make use of t h e sand blast m a y find some suggestions in our description a n d drawings. T h e sand blast devised by t h e writers has given excellent results i n marking Babcock test bottles. It is easy t o manipulate, economical a n d rapid. From t h e drawing it will be seen t h a t t h e manipulation is
+@SAND BLAST
very simple; t h e bottle t o be marked is placed i n a cylindrical receptacle (bottle holder), t h e bell-crank presses t h e bottle against t h e stencil, t h e air cock is opened a n d t h e sand forced against t h e stencil. At t h e same time t h e cylinder is rotated by t h e hand sufficiently t o expose t h e letters t o t h e blast; when t h e t u r n is made t h e foot-lever is released which cuts off 1
Bull. 122, Bureau of Soils, U.S. Dept. Agriculture, 1914.
