Mar., 1912
T H E J O C R N A L OF I X 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 .
that a code of ethics should be formulated and adopted b y the American Chemical Society. There are many instances which can be cited of unethical practices among chemists, such as: misleading advertisements and interviews in papers and magazines; the lending of certificates for advertising uses; the misuse of our science for the purpose of perpetrating frauds on the public, such as the evasion of a standard of purity or the sophistication of a product; slovenly and unreliable work sometimes revealed by impossibly low prices for analytical tests; expert testimony of a character discreditable to the witness and to our profession; a lack of courtesy towards our fellow chemists: a n d in this respect we stand far below the medical profession. The present committee of three should be retired, and a larger committee, of perhaps seven members, be appointed, representing the various branches of our profession, and with power t o draw up and recommend a code of ethics. Such work should be done deliberately and with the greatest possible discussion, which can not fail
227
to have a beneficial effect, in pointing out evil practices and elevating our standards of behavior. This subject has already been discussed at Indianapolis, Louisville and New York, and we believe that each of the several sections would do well to devote one night t o the discussion of this problem. We do not think that for the present, at least, it will be possible or desirable for the American Chemical Society to attempt the enforcement of a code of ethics, still less t o examine members with a view t o certifying their competency as is done by the Institute of Chemistry of Great Britain; but we do feel that the adoption of a carefully worked out code of ethics, prominently displayed in our publication, would set before us the standard of professional conduct, which, as members of the American Chemical Society, we would be expected t o follow, and which would greatly tend to emphasize our brotherly relations to fellow chemists and elevate the ideals of our profession. (Signed) A. C. LANGMUIR, C. F. MCKENNA, L. F. BROWN.
NOTES AND CORRESPONDENCE serted again as far as it will go, removed, the bleach transferred to a glass fruit jar, etc.” Now when material contained in a package varies appreciably I n the November issue of THIS JOURNAL (3, 861) in composition from the centre to the surface, the rejection of the Committee on Standard Specifications publishes certain a portion of the sample, representing a layer of z or 3 inches provisional rules for the sampling and analysis of bleaching all over the surface, has a vastly greater effect in modifying porn-der, together with a sliding scale of unit prices founded the average content of the accepted sample remaining than is on the percentage of available chlorine a t a base of 3 j per cent. generally realized. In fact the general adoption of such a sysThe directions for sampling there given certainly demand tem would introduce what is sometimes termed a “little joker,” criticism and discussion, not necessarily as regards their applithe influence of which may be highly prejudicial t o one of the cation to the particular substance for which they were recomparties t o a sale controlled by such a sample. Few seem to mended, b u t because they violate the basic principles of sampling realize the fact that a much larger portion of the contents of -assuming, of course, that the ideal sample aimed at is a segrea package is near the outside than is to be found equally near gated and relatively small portion of material, which shall the centre. have a composition exactly corresponding to that of the average To illustrate the last point it is simplest to consider a concrete mass sampled. example. Let us assume a cask or drum, exactly twenty inches On the other hand, the sliding scale established appears in diameter and thirty inches in length, both internal, the condistinctly favorable to the purchaser. tents of which are to be sampled (Fig. I). The following table shows, in the last column, the percentage of the total material SCALEOF PRICES, vemainzng, when a shell of varying thickness, ranging from 0 . 5 Multiplier for base Relative price per ton. to j.0 inches, is removed from its entire surface-such a portion Percentage. price per unit. as is virtually removed when a similar length is rejected from 31 0.74 22.94 65.5 32 0.82 26 .’24 75 a scoop or tryer sample.
A NOTE ON SAMPLING. B Y W. J. SHARWOOD.
Y
33 34 35 36 37 38 39
0.89 0.95 1.001 1.04 1.07 1.09 1 .lo
29.37 32.30 35 .OO 37.44 39.59 41.42 42.90
83.8 92.3 100.01 107.0 113.0 118.0 122.6
The specific directions for sampling are, in part, a s follows: “The sample shall be taken by boring a one-inch hole through the side of the cask, midway from the ends, or through the head near the centre. The sampler, which consists of a stout iron scoop, about three-fourths of a n inch wide and eighteen inches long, shall be inserted for two or three inches, withdrawn, and the bleach removed discarded. The sampler shall be in-
’ Base.
BASEDON A CYLINDER 20 B Y 30 INCHES. Diameter Approximate Height of Thickness of Area of volume of Percentage of shell remaining remaining CTOSSremaining of total discarded. cylinder. cylinder. section. cylinder. volume In. In. In. , Sq.in. Cu. in. remaining. 30 0 20 314.1 9423 ’ 100.0 0.5 19 29 283.5 8221 87.2 28 1 .o 18 254.4 7123 75.6 1.5 17 27 226 .O 6100 6.5 . O 2.0 16 26 200.6 5200 55.5 2.5 15 25 176.7 4418 46.9 24 3 .O 14 154 3700 39.2 CALCULATIONS
If, therefore, we reject a shell two inches thick, next the surface of the filling of a cylindrical con&iner twenty inches in
diameter and thirty inches high, the portion considered is od!55.5 per cent. of the total. I n the case of a smaller container the rejection of a shell of this thickness will, of course, leave a still smaller percentage-with a cylinder sixteen inches diameter, by tn-enty inches high, only 17 per cent. would remain. I n eithcr case, if deterioration. say to the extent of j per cent. of some constituent without change of weight, has taken place inlthe outer h-o-inch shell, the interior of the package remaining intact, then a sample taken Trith a tryer as directed will .indicate a percentage about 2 . 5 per cent. highcr than the true average content of the packagc when sampled. In the ease of a material suffering change from dccomposition, oxidation, or the loss of a x-aluable constituent, the p-chaser will, of course, suffer by the adoption of such a pro-
r -----I I
--I
taken Jvith a c?-lindrical tryer, reaching to or past its centre, ]vi11 she\.\- a perccntagc better than the true average, no matter in \!-hat direction the tryer is thrust. This form of tryer tends to take, in the c a x uf such a substance as bleach, a sample of too high a percentage, even if the surface layer is not discarded. This, also, is perhaps best shown by a concrete example: Assume a cylinder as Ijefore, twenty inches in diameter, and for simplicity's sake assurnc that no change of xeight occurs a n d t h a t no deterioration takcs place a t the ends of the cylinder, b u t only from the axis outward. Let thc central portion of the mass retain its original percentage of a certain constituent, say 36 per cent., lrhieh a t the circumference is diminished to 31 per cent. This is indicated in thc sectional diagram (Fig. 2 ) and i t is obvious t h a t a t two-inch intervals indicated
I
I
by B, C, D, etc., the percentages ,will be 32, 33, 34, etc., as there shoir-n. The true mean percentage over anyi-normal crosssection will be 31 36 - 31/3 = 32.67 per cent. The follon-ing table s h o m the percentage actually contained in a sample taken with a cylindrical core tryer reaching to the centre (F) and to various distances beyond it, and also the additional effect of discarding the outermost two inches from the sample.
+
I
P E R C E N T A G E S S H O W N BY C O R E S A V P L E (SEE
I
_-
Portion sampled 4F AG -413
AJ A I; AL
\'
FIG.
ACTUAL
PERCENT-
GIVEN COXSTITCENT, 32.67 P E R C E S T . I . Preserving entire sample. 11. Rejecting outer 2 inches. A G E OF
>_
7
Percentage of constituent in sample. 33.5 33.53 33.93 33.75 33.72 33.5
Portion sampled UF BG BH
BJ BK u I
-be found in the literature, all of which require considerable time for sedimentation, and, usually, quite a n amount of alcohol, which makcs purification expensive. X great many have used a water extract of commercial litmus without further purification, neutralizing to meet their requirements. This gives a paper which is satisfactory for some purposes, but the red paper is usually rather impervious to \rater, and the large amounts of soluble salts Ivhich it contains cause reactions in the paper \i-hich arc often deceiving. These \-arious difficulties havc: led to the use of the chemically pure litmus xhich is sold b>- the various supply houses and can bc prepared iri about one-quarter of the time required by the ordinary substance. Although the chemicall>- pure litmus is listed a t ten times thc value of the commercial product, its coloring strength is so much greater that the final cost is never more, and in some cases is less. Continued trials have shon-n the follo\ving to be a \-cry satisfactory grade of litmus paper for all purposes, i1-hether laboratory or manufacturing, and the product \rill be found more delicate than most litmus papers o n the market. For blue paper, I . q pcr cent. of chemically pure litmus is dissolved in clistilled 1T-atc.r ivith constant shaking for about one hour. This solution is set aside over night, carefully decanted from thc small amount of sedirncnt, and sulfuric acid added. drup by drop, sufficient to reduce alkalinity to such a point t h a t a piecc of filter paper floated on the top and thcn dried
will assume a \-cry perceptible red color :aftcr being suspended 2000 h?-drochloric acid. one-half minute in To make red litmus paper a I .o per ccnt. solution of cheniically pure litmus is required Tvith thc addition of sulfuric acid until such a degree of acidity is reached t h a t a very perceptible reaction Jvill take place when paper floated and dried as before is suspended one-half minute in N / p o o caustic soda solution. Time of exposure to these standardizing solutions is round to be as important a function as the degrce of acidity or alkalinity of the paper. The above-mentioned degrees of sensitiveness arc closc to the practical limits, for if the papers are made more delicate they cease to bc red and blue. hut becomc lilac or neutral. The filter paper used is any smooth compact qualitative paper sold by the chemical supply houses. The bcst manner to saturate the paper Ti-ith litmus has been found to cut i t in strips about seven inches wide and to tlran the paper over the surface of the litmus solution, Trhich hns previously been placed in an ordinary shallow square-cornered cnamcletl bread-baking pan. Thc paper is held I)>- the ends and first touched t o the surfacc of the liquid, about t l r o inchcs €roil1 one e n d ; then the other end is released and the paper d r a n n don-n across the cdgc of the pan. Surface tension holds thc paper to the liquid, yet only one side of the paper is alloired to touch the solution, and drawing across the side of the pan takes aim!- an?- excess. Thc strips arc hung up to dry by pinning the blank ends over lines qtretchetl in some con\-enic.nt place. The paper \rill be lound very unifortii. as just sufficient solution will have bccn takcn up to dye all the sheets of the sainc shade. Onc liter of solution \rill make one hundred shcets seven inches b y tn-enty inches in sizc. These sheets may be rolled u p or packed airay in proper containers to protect them from the air. nntl cut in strips of eon\-enicnt size for use shortly before they arc neeilctl. I I X c mouthed. glass-stoppered bottles are found very conveiiicut for holding the small strips for daily use. Great uniformity is secured by making up large batches a t a time, and thc method a l l o w for closest similarity of succeeding batchcs.
E.
n-. I i I C r i .
PERILLA OIL. Product from the seed of Pt-rilla ocivzoidi,r (Nat. Ortl. Lal)iateae), an indigenous plant of India, China :ant1 Japan. Perilla oil is very similar to t h a t of iinseetl. In Manchuria, i t is uscd for edible purposes. The Japanese use the oil lor \vatcrproofiiig paper umbrellas. and lor preparing transparent paper for i v i i i do\rs. I n the colder portions of Japan. the plant is groi\-n a s LL fie1,l crop. The annual production oi d is about ~ o o . o o ohushel\. A bushel of seed gives up a galrim oi oil, .ii-orth ;o c m t s 1)er gallon. U. S.Consul Samnion, 1701;ohatn:i, Japan. in 1910 sugges,tetl the introduction of this plant intu the United States. Folloi\-ing this suggestion. a small quantity of the seed \vas iinported from Japan. During the season of I ~ I , I thii plant \vas gro\\-n a t ilkron, Ohio. Seed \rere sonm April 15th: 1)lants came u p 10 days later; growth slo\v; h1ooi;letl .\ug. j ' to Sept. l i t ; harvested Oct. Ist, after plants had Iwm injured l>>- l ~ - m t . Plant resists light frosts, b u t cannot resiyt drought. On the dry, sandy soil of n'est -Ikron, thc plant dit1 not d o xcll. On the damp, claj-ey soil the growth iras much hetter. S-ield of seed based on very small arca is about loo pounrls per acre. The seed of this Ohio-gro\rn perilla \vas 20 per ccnt. lighter, per equal volume of seed than the parent s e d . The crop did not fill irell; about 80 per ccnt. of the seed pockcts
