a WEIGHTS AND MEASURES Regulations Relating to Cream Test Scales and Bab- cock Milk and Cream Test Bottles Prescribed by J. Q. EMERY, Ex Officio State Superintendent of Weights and Measures of WISCONSIN ISSUED MARCH 3, 1914 " 4 4 Wale a v tee ! aN ! ; ay) ; ( i) y i f ; - i e i ivi f t . _ fine ‘ 1 a t 7 . 4 7 ’ é Pi ; ¥ 4 { é ‘ f ‘ 1 ‘ 1 v. } . ¥ : N a i \ 1 ») ' t \ i t a i hel r t . is rt y ,! i i ] ; . ‘ fi nl te 4 / iY ¥ % y : ay “ ; 4 ‘ 4 } \ \, , \ ) / ) . : NS i f \ ma . ; . } “4 ; a caw. j \ cm ' ‘ i] ‘ i} f ‘ ° ti | , | 0. OF B, | Srna NOV 18 1914 4 , Y ‘ { r Ve { { : 4 ( bare } ¢ ‘ ~ r d i ePa a a Paw aoe r ay \ ' 1 ‘ i | » { his Ps ¢ { ' ih , 4 er 1 \ ‘ ' 1 4 | é q \ i ) n . 2 ' STATE OF WISCONSIN OFFICE OF DAIRY AND FOOD COMMISSION AND WEIGHTS AND MEASURES. Madison, January 17, 1914. To Wisconsin Sealers of Weights and Measures: Subsection 6 of section 1659 of the Wisconsin statutes con- tains the following provision: ‘““The superintendent of weights and measurers. shall issue from time to time, regulations for the guidance of all sealers, and the said regulations shall govern the procedure to be followed by the aforesaid officers in the discharge of their duties. In said regulations he shall prescribe the amount of tolerance to be allowed.’’ In obedience to the requirements of this statute, the following regulations are prescribed for the guidance of sealers of weights and measures in the performance of their official duties so far as the same relate to the subject of Babeock milk test bottles, standard Babcock pipettes, Babcock cream test bottles, and cream test and butter fat test scales. Bascock Mink TEst Bort.ueEs. Babeock milk test bottles complying with the following spe- cifications shall be sealed: The standard Babcock test bottles for milk shall have a capacity of two cubic centimeters for each 10 per cent marked on the necks thereof. The necks of the standard Babcock milk test bottles shall be eraduated from zero to 10 per cent and the graduated scale shall be 75 millimeters in length, with an allowable tolerance of 5 millimeters either above or below. The graduated scale shall be divided into per cent and fifth per cent divisions. The fifth per cent graduation marks shall be not less than 3 milli- Tyne D. Type C., Type B. ial Type A. — | iT all Hii Milk Test Bottle. | | meters in length and the per cent graduation marks shall be not less than 116 millimeters longer than the fifth per cent graduations. Each per cent graduation shall be numbered and the tolerance for the entire graduated seale or for any part thereof shall not exceed one-tenth of one per cent. The necks shall be cylindrical for at least 5 millimeters below the lowest and above the highest graduation mark. The top of the necks shall be flared to an interior diameter of not less than 10 millimeters. The capacity of the bulb up to the junction of the neck shall be not less than 40 cubic centimeters. The total height of the bottle shall be between 150 and 165 millimeters. Each bottle shall bear either a ground surface for identifi- cation number or a permanent identification number. Subsection 1 of section 1494aa of the Wisconsin statutes pro- vides as follows: ‘ “In the use of tthe Babcock test, the standard milk measures or pipettes shall have a capacity of seventeen and six tenths cubie centimeters, and the standard test tubes or bottles for milk shall have a capacity of two cubic cen- timeters for each ten per cent marked on the necks thereof ; cream shall be tested by weight and the standard unit for testing shall be eighteen grams, and it is hereby made a misdemeanor to use any other standards of milk or cream measure where milk or cream is purchased by or furnished to creameries or cheese factories and where the value of said milk or cream is determined by the per cent of butter fat contained in the same, or wherever the value of milk or cream. is determined by the per cent of butter fat con- tained in the same by the Babcock test.’’ Referring to the foregoing provisions of law and other laws prescribing the duties of the state superintendent of weights and measures, Attorney General Owen has rendered the following official opinion : “The fact that the statute says that the standard test tubes or bottles shall have a capacity of two eubie centi- meters for each 10 per cent marked on the necks thereof imphes that the necks should have marked thereon the 10 per cent mark. I believe that a so-called milk test bottle having only 8 per cent mark on the neck is, therefore, not in compliance with the provision of this law and you are, therefore, instructed that you would not be warranted in approving the same.’’ | | STANDARD BABCOCK PIPETTES. The standard pipettes shall have a capacity of 17.6 cubic centi- meters. The total length of pipette shall be not more than 3380 mill- meters (1314 inches). The outside diameter of suction tube shall be 6 to 8 mill- meters. The length of the suction tube shall be 130 mulli- meters. The outside diameter of the delivery tube shall be 4.5 to 5.5 millimeters. The length of the delivery tube shall be 100 to 120 millimeters. The distance of the graduation mark above the bulb shall be 30 to 60 millimeters. The nozzle shall be straight. When filled with water at 20° C. delivery shall be in 5 to 8 seconds. The tolerance shall not exceed .05 cubic centimeter. A pipette having a capacity of 18 cubic centimeters or hav- ing any other capacity than that above specified, namely 17.6 cubie centimeters which is the only pipette that complies with the terms. of the law, must not be sealed. : Note. Section 1494aa of the Wisconsin statutes contains the following provision : ‘“Cream shall be tested by weight and the standard init for testing shall be eighteen grams, and it is hereby made a misdemeanor to use any other standards of * * * cream measure where © * * cream is purchased by or furnished to creameries or cheese factories and where the value of said * * eream is determined by the per cent of butter fat contained in the same, or wherever the value of * * * eream is determined by the percent of butter fat contained in the same by the Babcock test.’’ Bascock CREAM Test BOTTLES. Babcock cream test bottles of the following types and com- plying with the following specifications are to be sealed: ~ Type A. Thirty per cent, 18 gram, 6 inch, 14 per cent grad- uations. Each 5 per cent on the neck of the bottle shall rep- resent a volume of 1 cubic centimeter. The neck of the bottle shall be graduated from zero to 30 per cent and the graduated seale shall be 75 millimeters: in length, with an allowable tolerance of 8 millimeters above or below. The graduated scale shall be divided into 5 mar oe per cent, 1 per cent and 4% per cent divisions, The 1% per cent graduation marks shall be not less than 3 millimeters in length. The 1 per cent graduation marks shall be not less than 114 millimeters longer than the 14 per cent graduations. The 5 per cent graduation marks shall be not less than 114 millimeters longer than the 1 per cent graduation marks. Each 5 per cent graduation shall be numbered. The allowable tolerance for calibration shall not exceed 14 per cent for the entire graduated scale or for any part thereof. The capacity of the bulb up to the junction of the neck shall be not less than 40 cubic centimeters. Each bottle shall bear either a ground glass surface for iden- tification number or a permanent identification number. The neck shall be cylindrical for at least 5 millimeters below the lowest and above the highest graduation mark. The top of the neck shall be flared to an interior diameter of not less than 10 millimeters. The standard unit for- testing shall be 18 grams. The total height of the bottle shall be between 150 and 165 millimeters (57 and 614 inches). Type B. Thirty per cent, 18 gram, 9 inch, .2 per cent grad- uations. The neck of the bottle shall be graduated from zero to 30 per cent and the graduated scale shall be 125 millimeters in length, with an allowable tolerance of 10 millimeters either above or below. The graduated scale shall be divided into 5 per cent, 1 per cent and .2 per cent divisions. The .2 per cent grad- uation marks shall be not less than 3 millimeters in length. The 1 per cent and 5 per cent graduation marks shall be not less than 1.5 millimeters longer than the .2 per cent graduations, The allowable tolerance for calibration shall not exceed .2 per cent for the entire graduated scale or for any part thereof. The total height of the bottle shall be between 210 and 225 millimeters (814 and 87% inches). All other specifications are to be the same as for 7'ype A. Type C. Forty per cent, 18 gram, 6 inch, 14 per cent grad- uations. The neck of the bottle shall be graduated. from zero to 40 per cent and the graduated scale shall be 75 millimeters in length, with an allowable tolerance of 8 millimeters either above or below. sj a All other specifications are to be the same as for Type A. Type D. Fifty per cent, 18 gram, 7 inch, 1% per cent grad- uations. The neck of the bottle shall be graduated from zero to 50 per cent and the graduated seale shall be 105 millimeters in length, with an allowable tolerance of 10 millimeters either above or below. The total height of the bottle shall be between 180 and 195 millimeters (71g and 7°34 inches). All other specifications are to be the same as for Type A. Type E. Fifty per cent, 18 gram, 9 inch, 14 per cent grad- uations. The neck of the bottle shall be graduated from zero to 50 per cent and the graduated scale shall be 125 millimeters in length, with an allowable tolerance of 10 millimeters either above or below. The total height of the bottle shall be between 210 and 225 millimeters (8144 and 8% inches). All other specifications are to be the same as for Type A. Referring to the provisions of section 1494aa of the Wisconsin statutes hereinbefore quoted, Attorney General Owen has render- ed the following official opinion relative to 9 gram cream test bottles : ‘Under this statute it is provided that ‘cream shall be tested by weight and the standard unit for testing shall be 18-grams and it is hereby made a misdemeanor to use any other standards of milk or cream measure,’ ete. As 18 grams are expressly mentioned as the standard unit used in testing, and as no mention is made of a 9-gram standard unit, | am of the opinion that only the 18-gram cream test bottles can be used and the 9-gram cream test bottles should be econdemned.”’ CREAM TEST AND Butter Far Test Scaues. The scale shall be provided with a graduated plate of at least ten divisions over which the pointer plays. The pointer shall reach to the graduated divisions and shall terminate in a fine point to enable the readings to be made clearly and distinctly. The ciear interval between the divisions on the graduated face shall not be less than .05 inch. ~ —9I— Beam scales and trip balances provided with knife edges and bearings shall be provided with leveling screws and an attached level. The scale shall be so constructed and adjusted that when the pans are released or disturbed the pointer will return to rest at the zero mark. The addition of 32.4 milligrams or one half grain to the scale when loaded to capacity shall cause a movement of the pointer at least equal to one division on the graduated face. The tolerance either in excess or deficiency when the scale is fully loaded shall be one grain. Weights. A tolerance of 20 milligrams is allowable in 18 gram weights and 10 milligrams in 9 gram weights. The man- ufacturers’ tolerance shall be one half this amount. Note. To avoid liability of penalty for violation of the weights and measures law by the use of any unsealed weight, scale, measure or measuring apphance of any description, in- cluding new applances,-or any such appliance that has not been sealed within one year, owners of the same should give notice in writing to the state superintendent of weights and measures, Madison, Wis., or to the city sealer if in a city hav- ing a city sealer of weights and measures, of the fact that they have such weight or measure or weighing or measuring device, fiving a deseription of the same and its location. See subsection 3, section 4432 Wisconsin statutes. 2 oa Cire ; Co Dairy and Food Commissioner, Ex officio State Sime en dent of Weights and Measures. Cina Quast! OFFICE OF Dairy AND Foop CoMMISSION AND WEIGHTS AND MEASURES. Madison, Wis., March 4, 1914. To Cheese Factory and Creamery Managers, Cheese Makers and Butter Makers:, Paragraph 3 of section 1659 of the Wisconsin statutes re- lating to weights and measures places a general supervision of all weights and measures and weighing or measuring devices of the state in the hands of the state superintendent of weights and measures. It further provides that he or his inspectors by his direction shall, upon the written, request of any citizen, firm or corporation, or educational institution of the state, test or calibrate weights, measures, weighing or measuring devices, and instruments or apparatus used as standards in this state. Under the provisions of this act, owners of creameries and cheese factories may send to the office of weights and measures at Madison, Wis. any Babcock milk, cream, or, butter test bottles, any milk pipettes, and any scales or weights used in the weighing of cream samples, and the same will be tested. No fees are charged for testing. Many managers are now or- dering their new supples sent direct to the office of weights and measures for testing and sealing, thus insuring accuracy before being put to use, with little or no inconvenience. In sending in old glassware, it is best to send only part. of the supply on hand at one time, as sometimes several weeks may elapse before the glassware can be returned. In sending apparatus for testing and sealing the following rules should be complied with: 1. Address all packages to J. Q. Emery, Office of Weights and Measures, State Capitol, Madison, Wis. The name and address of consignor should be placed on the outside of the package. 3. Transportation charges on packages should be prepaid. bo ee Sg fe 4. lf consignor desires package to be returned by parcel post, postage should be enclosed in letter to pay for return of same. 5. Bottles to be tested must be thoroughly cleaned before sending, so that all sediment or deposit on the inside of the bottles is removed. No tests will be made of glassware that is not thoroughly cleaned when sub- mitted. 6. Extreme care should be exercised in packing such glass- ware or scales for shipment, as this department will not be responsible for breakage. J. Q. EMERY, Dairy and Food Commissioner, Ex officio State Superintendent of Weights and Measures. CREAM TEST SCALES AND BABCOCK TEST BOTTLES. By F. P. DowniNncG, Chief Inspector of Weights and Measures. CREAM TrEest SCALES. Many articles have been published upon the testing of milk and cream by what is commonly known as the Babcock method. In obtaining the percent of milk fat by this means the operator starts with a known volume or weight of the sample, places it in a graduated milk or cream bottle, treats it with sulphuric acid and then after centrifuging or whirling the bottle a defi- nite period, reads the percent of fat directly from the bottle. In making the above test, skill and experience are required to secure accurate results. But no matter how careful the op- erator may be, it will be imposilbe for him to get correct results if he is not provided with accurate glassware and_ sensitive and accurate scales. In the past, the creameries of the state have been obliged to depend largely upon the advice of salesmen when ordering supplies and apparatus with which to work. This has resulted in the purchase of certain types of scales entirely unfit for the purpose for which they were purchased, and the use of such scales has been the cause of great errors and heavy losses. There was a time when an 18 ec. cream pipette was considered sufficiently accurate to use in making cream determinations. But when it became known that such a pipette would deliver 17.9 grams of a 10% cream and only 15.8 grams of a 50% cream, the cream pipette was replaced by various types of cream test scales. The wide range in the specific gravity of cream showed the unreliability of the use of a pipette. Every intelligent creameryman is now aware of this. But it is not so generally known that errors approximately as great as those obtained through the use of the cream pipette may be obtained by the use of inaccurate and insensitive cream test scales. The better class of books on the testing of cream give minute explanations to the operator concerning various ways in which —13— mistakes or errors in the reading of the fat content of the cream are produced, the proper temperature at which to take readings, the proper method of reading the meniscus, the strength of the acid to be used, and the number of revolutions made by the centrifuge. These and other essential details are deseribed, but little or nothing has ever been published with regard to the errors that arise through the use of inaccurate cream test scales. Investigation shows that many of the mistakes now made in the creameries in this state in the determining of the fat con- tent of cream are due, not simply to the causes enumerated in the paragraph above, but to the use of scales of improper con- struction. Frequently creamerymen find themselves unable to obtain duplicate tests in the determination of the percent of cream. Frequently farmers send their cream to the state dairy and food commission, to the university, or to the county train- ing schools for analysis and the results obtained differ from the readings given at the factory. In a number of instances, this difference has been found to be due to the use of cream scales that are not sufficiently sensitive. For the purpose of determining what types of cream scales were the most accurate and the best adapted to weighing a hine or eighteen gram sample of cream, state inspectors of weights and measures were sent to various creameries of the state to inspect the scales in use and to check up the weights obtained upon such scales by the creamerymen. The butter- maker at the creamery was asked to weigh a given number of samples of cream on his seale, following the methods pursued by him in his daily work at the factory. In practically every instance, greater than usual care was taken in making the weigh- ings. The bottles containing the samples of cream were then securely corked and brought to the office of the state depart- ment of weights and measures at Madison, where they were re- weighed on a delicate Becker office balance sensitive to .1 milligram. The results obtained were indeed surprising and are given in Table I. ast ph a T000°8T ggc0" 016° LT S280 ST i 81 % £266" LT LT00° €166 "LT 0&66° LT P See v4 S66 LT £00" S066" LT 0866" LT i 81 Fe fF0°8T FS0° O8T0°ST 02L0° 8T f ‘ “A 6676 ° LT 9L9T 6FS8" LT S200 81 G 8T | % [00°81 TL10° £666" LT S9T0"8T G 8T a tema £9081 MSs Pés0r ST00°8T 6f01' ST Pp 8 I 686° LT 8L° Itt’ f66° LT ISET 81 iy 8T I 61°87 STL &¢6¢'T CSer LT GLTL 8ST 8 $I beast ea é10'°8T SIT G10c° 0L26 LT SPET 8ST 9 8T é 910°8T 89°¢ FEsp’ PLEO LT POET 8ST 9 8 é Ig “81 LY OFFS" 06F6" LT €6L° 81 p $I L 16° LT pL Ss 6EL9° F6CS LT £02 81 G 81 pi taaalige, 5 II 81 GO" s €869° 69F8" LT SPOS" 8T G $I é P92 8T a6 P O&82" LEG LT 0¢L 81 g 81 § 816 £9°6 8198" 1892°8 6GE9 6 G 6 8 8h LT Cord 66cr" TI€L° LT OFST' ST 8T 9 86° LT oss PIE9" 6S19 LT 99Fe 81 8 $I 6 {SIO Mm qysiam | Suneas SWWIS | poysram| ‘sues SUTeIs 81823 |-11e8A Jo | Jo uoly | Peureaiqo “peureiqgo | ssjames ur oY J025% hues tag -vae, | Ise | yYsIOM qequiny | asavyg SseueAn -LdA VW qsemoyT | qseusry -|suag “"""fOpUrA\ “UTA, “**.19PUTM “UA, “*""TOPUlA\ “TOA, *"1ayoj4e0g “YL “**“cdOsdwmouLy, * ~ -TOpUrM “WA ) ‘apt “£19 orarwioze jy | ‘0D SATB Td “AD uvueyong ‘Oo “Lou -leyulog “J °H) "2 saXO]q “UA ( “*“sqreqoy uyor “ATO UOPTLL Iaqaveg WZ Yorory “royoqe0g “Af “AQ preyporg “'''STapUeZ’ WH “£19 plegsur yy + aoe SO “+ HOSTpRyy "*** DOSTpRTY "* UOSIPR IY “*** UOSIDR IN “AYO DP. Slory “"** COSTIPR ‘QIU BUOZe IT "SULET SSOID "140 PLOY *@l[1AUeTaH ** OT TAU OTOH] ) mosaDy WT Sea “ayo + OOT1878 AL | **y004SMI0D |" peoyporg ‘SUTe[q SSOID "*'-OSIPR IAT Aq poysto Ay 4@ paysiom WedI9 00ST “ON 91330q T STST ‘ON uolsdoy, 8T990q oa ’ ” UOISIOT, ™N ofr oN aj0q Ff e199 “ON IIUWIOLY, 8[}904 ZT UOIS1O J, "09 ‘ON TaUMIAOA,L 6F6 “ON SyURGATEY 811304 F ss *y ry { ar) ory 7” | : ” ” 219 ‘ON paeweec Tonal 9[310q rat ” ” a ” ¢008 ‘ON UOISIOT, e[}30q ZI | PI UW 81 WoW &T UW ¢ “dy IT “Geet ACTIN &T “WOW Og “Ue cz uel fl oune fleuny’ Te AP ¢ dy 8T “G9 G ‘1dV Té “G94 0g ‘uel 8¢ uel’ €I6l a[eos Jo dA, “UPSHOISIAL UL 08) U2 SaDIG j8aT Wau fo sadhy s NOWD{ UO WnaLQ fo ‘T aay, Burybrayy ay. ur powuniqg syneaaz = en = =e NIOSSID SOE COR es a fe A careful study of this table reveals the fact that the more sensitive the scale the smaller the error resulting in weighing the cream. For instance, in test No. 1 the error of variation in duplicate tests amounted to 3.5%. In test No. 18 the variation was only .31%. The first scale had a sensitiveness of nine grains, whereas the latter was sensitive to one-third grain. In test No. 3 made at Brodhead 9 gram samples were weighed and the varia- tion was 9.64%. It is clear from this that the smaller the .charge the greater will be the percentage of error accruing through the use of a sluggish scale. If a nine gram sample had been taken in test No. 1 instead of an 18 gram, the variation in duplicate tests would undoubtedly have been about 7%. Tests Nos. 8 and 9 made at Helenville by Messrs. Moyes and H. L. Bornheimer show the personal factor in the use of a scale. In this instance Mr. Moyes, the buttermaker, weighed six samples of cream upon the scale, following which Mr. Bornheimer weighed the remaining six samples. On checking up the weights obtained by these two men, it was found that the variation in weighings in the case of Mr. Moyes amounted to 2.68%, while in the case of Mr. Bornheimer the variation was but 1.15%. The types of scales used in making the tests given in Table I were the twelve bottle torsion balance No. 3005, the twelve bottle Troemner balance No. 612, the four bottle Fairbanks Troemner balance No. 6612 with hanging pans, the four bottle torsion balance No. 1530, the two bottle torsion balance No. 1515 and the one bottle torsion balance No. 1500. (See Illustra- tion). The figures show that accurate results are unobtainable through the use of the twelve bottle torsion balance 3005, the twelve bottle Troemner balance No. 612, and the four bottle Fairbanks balance No. 949 when the same are sluggish and in- sensitive in their action. Scale manufacturers concede that it 1s almost an impossibility to make a twelve bottle scale with overhead pans which will remain sensitive to 14 grain and not show a greater error at full load than one grain. The figures in Table I likewise show that the specifications for cream scales must differ radically from the specifications applied to the ordinary commercial weighing appliances used in grocery stores and meat markets. It is not necessary for a grocer’s balance to be sensitive to one or two grains. He weighs his groceries in large quantities. An error of one grain in the Btls, Sod MN yr weighing of a pound of tea would be an error of only 1/7000 of the load while an error of one grain in the weighing of a nine gram sample of cream would be an error of 1/139 of the sample, the proportionate error being fifty times as great in the weight of the cream as it is in the weight of the tea. To show the losses resulting through the use of inaccurate scales, a few cases are cited, taking the figures from Table I. In the case of H. M. Zanders of Cross Plains, the average weight of the tests was 17.48 grams, the error being minus .52 grams or 2.89%. The error on 10,000 Ibs. of butter fat would amount to 289 Ibs. At 25 ets. a pound for butter fat the loss to the patrons would be $72.25. In the case of test No. 7, John Roberts of Fort Atkinson, the average weight of the tests was 18.31 grams, the excess weight being .31 grams or 1.72%. The error on 10,000 pounds would be 172 pounds. At 25 cts. a pound the loss to the creamery would be $43. Tn test No. 3 at the Brodhead Creamery the highest reading of the nine gram sample obtained showed an error of .6359 grams or 7.06%. The loss to the creamery on 100 pounds of butter fat at 25 ets. a pound in this case would amount to $1.76. The lowest individual reading obtained at the Brodhead Creamery was .2319 grams short of 9 grams or 2.57%. The gain to the ereamery on 100 pounds of butter fat at 25 cts. a pound in this case would amount to 2.57 pounds valued at 64 cts. By using scales sensitive to 14 grain or less, the errors are very slight, almost negligible. The results obtained in Table I applied to scales in actual use, some of which were a number of years old. To be absolutely sure that the unfitness of the types of scales mentioned in Table I is due largely to the inherent construc- tion of the scale and not to the operator of the scale, nor to im- perfections brought about through use, manufacturers of cream test scales were requested by the state department of weights and measures to submit different types of new scales which they manufactured. The manufacturers were perfectly willing and glad to codperate with the department in this matter and in each case a loan of the different types of scales manufactured was made to the department. wer sip ye 6610°0 6666 0 %86 0 %Sh'0 S89" 0 0680°0 $1081 8600 °8T [69081 0610 8I S6S08T 0996" LT ¥oL0° 81 OLF0°8T FE80 ST 0800°8T 0¢20°8T 0996" LT 00€0°8T GLL6 LT 0660 °8T 00TO 8 OFLT SI 0260°8T OBLI°SI riniajalateisiovcfehatareqe COr0' SI Roteieteletelaistelsswiete 0020°8T OTSO'8T “UTIL 8Z “UIU JZ 0 0 0 G “6199 “ON ou . ‘ON ~ULBOLT, sued eae nin Si SUSUR Y 98[930G | 919900 Gr ysis’ 0 EEE 0009°0 AGIL St 0GE0'8T O99T SI OLSE SI O89I'8T 0S90°8T GLST SL 00218 OLGL° LT Ist 81 “ULUH JT “66 “ON SHUBCATE 91930 F esc8" 0 %60°S 0L16°0 O0ZT “ST 0668" ST 0996" LT O&F0 8 08c0°8T 006° LI CZL0 81 000° 8ST 0286" 21 T6SP 8 0106 8 F896 81 40968 “UTUL gt “0C6 “ON SHURA IT a1}10q ZI Fr6I 0 MFO T S8sT 0 667081 16S0 ST C696" LT $o00' 81 FEO St 020° T O90 8 O9E1 ST 0&96° LT 0¢00°8T CTST 8ST 00F0° SI 0.90°8T “UyUL €% ‘09 “ON TIUWMOL “Salnsvayy PUD 8$90°0 1¢0°0 8F90°0 %80'T %9L"0 %1E"0 SO6T‘0 #9E1°0 £%10°0 1010" 81 6@10' SI 2080" SI 1790°81 8cI0'ST 90¢0°8I CZ00'8T GGG0° ST €290' SI TIT SE #260° SI F100°8I $166° LI 710° SI F650 SI 09¢6° LT 02Z0'8I 0966" JT 09°62 O916° LT 0%66'21 QTL ST 08¢0°8I (065° 2 0000°8T 080081 OF00' SI 0ge0' SI 0666" LI 0&£0" SI 6686" LI ©100°8I ©)#0'8I 0@L6°21 0010" SI 0F00'SI 0826" ZT €g00° SI 0¢10°8I “UTUL ¢% “UTU 8z “ULUL ¢% % 0 60 ¢ yy, 60 ‘Z1I9°ON | “GIST “ON | ‘OgcT ‘ON T9UWOOL uOISIOT, UuOIsIO,[, atiog zt | elq300z aqii0q F eo See 066° 21 TLI4 SE cele LL FIG Sl PL40 Sl 0GL6 LT OLI6 20 cg6s" LT c¢10 81 Coil st C219 ZT OFIT St 0628" LT “UIT 0Z “C00 “ON UOISIO,[, 911104 BI See CAS TEE Ld Ul MOIST -Ip euo &q 19a3UIOd JO suIpvor snutw pue suid 0} enp 10117 7775 7222""" STOMVIIBAO JUSOLEg ce = Voereeeeeeee ss SUBS UL UOTIBIER A ““SUIBIS “SSUITSIOM JO O5R.10A VW fess *s90u87Bq BOIZO UO Sut -YsjeMor GQ paureiqo sureas UL WIRAID JO VITUS JO IYSIOA\ bitte eee sees seeee sees sees eens gor -W8S ZI USIOM 0} pedInbed ouypy, "+" SULR.LS “SpBOL [[NJ ye 1011 '’SUIRIS ‘[ROOIdIDNY AJIPIGISUIS | | +++ 9[BOg 4Saq, WIReID Jo ed4y, | sy bray fo quawujundagy aynygy ay, paunoT saypog woaig nayy fo sadhy, quasfiq wo wnat) Jo buyhiay ay2 ue paumiag synsoxy Val takes Yh ae BS [je Table II gives the results of the weighings made upon these new scales. Twelve 18 gram samples of cream were very care- fully weighed upon each type of scale, extreme care being taken in placing the cream in the Babcock bottles not to add an excess. If a few drops of cream in excess were accidentally poured into the bottle, the same were removed so as to bring the scale back as near as possible to a perfect balance. The samples were then | reweighed upon the Becker office balance and the variations in weight recorded. The results obtained again show that the more sensitive the scale, the more accurate the weighings recorded and the less the variation of duplicate samples. By studying the variation of the duplicate weights in grams, it will be observed that the greatest variations were obtained upon the twelve bottle Fairbanks cream test scale No. 950, the four bottle Fairbanks eream test scale No. 949 and the twelve bottle torsion balance No. 3005. In these experiments the twelve bottle Troemner balance with hanging pans, No. 6612, is the only type of twelve bottle cream test scale that gave reasonably accurate results. The errors resulting through the use of the twelve bottle Troemner No. 612 and the Troemner scale No. 60 are almost identical. It will be noted that the twelve bottle Troemner No. 612 submitted to the state department of weights and measures is an exceptionally sensitive scale for one of this type. It seems necessary at this point to explain the meaning of the term sensitiveness. More technically speaking, this term should be called the ‘‘sensibility reciprocal’’. It as defined as the weight in grains required to move the pointer over one scale di- vision. Where the scale was not provided with an indicator as was the case in the twelve bottle Troemner No. 612 the sensi- bility reciprocal was considered as the weight which when placed on the pan would move the pointer a distance equal to the thick- ness of the pointer, or about three millimeters. Comparing the results obtained on the twelve bottle Troemner No. 612 in Table II with the results obtained in Table I, it will be observed that the sensitiveness of this scale decreases rapidly with use. This is no doubt due to the fact that there are a large number of friction points. Exposure to moisture rusts the con- necting rods beneath the base of the scale, producing sluggish- ness in its action. ° Attention is called to the figures in the last row of Table IT in which the error due to a plus or minus reading of the pointer one scale division is recorded. These figures are obtained by multiplying the sensitiveness of the scale in milligrams by two. In the ordinary operation of cream test scales the operator un- doubtedly frequently overloads or underloads his scale an amount which would cause the pointer to deviate one division to the right or left. In doing this the error for the different types of scales depends strictly upon the sensitiveness of the scale. By comparing the figures in this row with the figures shown in the row indicating the actual variation in grams of the dupli- cate weighings an idea is given of what proportion of the vari- ation is due to the use of a sluggish scale and what proportion is due to the personal element. There seems to be a prevailing opinion among creamerymen of the state that the use of a twelve bottle cream test scale re- sults in the saving of much time. To determine just what this saving would amount to a record was kept of the number of minutes required to make twelve weighings and the figures are recorded in the third line of Table II. The results show that the more sluggish and insensitive the scale the less time is re- quired in making twelve weighings. It will be observed that twenty minutes were required to make twelve weighings on the twelve bottle Torsion balance No. 3005 and but twenty-three minutes in weighing twelve bottles upon the four bottle torsion balance No. 1530. This time included the balancing of the four bottle balance three times. While the ability to make rapid Weighings on a cream test scale is important, nevertheless accur- acy should never be sacrificed for speed. While it required three minutes more to make twelve weighings on the four bottle torsion balance than it did upon the twelve bottle torsion bal- ance, the percent of variation in the twelve bottle balance was about ten times greater than that obtained in the use of the four bottle balance. A cream test scale should fulfill the following requirements :— It should be sensitive to one drop of cream, which is approx- imately thirty-two milligrams or one half grain. The maximum error permissible at full load or less should not be in excess of 64.8 milligrams or one grain. If of the beam or lever type, it should be provided with leveling screws and a level so that the errors due to weighing on a scale out of level can be avoided. If provided with a tare weight this weight should not be so heavy that it is difficult to bring the scale into balance through f= Oye a very slight movement of the tare weight. A tare weight which moves upon a threaded rod is much easier to manipulate than one that slides along a smooth rod. The weight of samples of cream should not vary on different parts of the pan, which is found to be the case with some of the twelve bottle cream test scales. The scale should be provided with a pointer which plays over a graduated indicator. It is extremely difficult to use a scale with two blunt pointers, such as are found in the twelve bottle Troemner cream test scale, and obtain accurate results. The scale should respond quickly so that time will not be lost in the operation of weighing. In order that accurate testing be done in creameries, the op- erator must be provided with proper utensils. It is of the high- est importance that the scale be accurate and sensitive. It must be remembered, however, that even if a new scale does weigh accurately it will soon become sluggish and inaccurate if it 1s not properly cared for. Comparatively few creameries give proper care and attention to the cream test scales in use. They are left exposed in a damp, room and become rusted. Dirt and dust accumulate on the bearings. The weighings are fre- quently made upon surfaces that are not level. A scale, to weigh accurately, must be kept clean and free from the moisture and dirt of the factory. The life of the scale could be greatly pro- longed if the operator went to the slight additional expense of purchasing a glass frame or cover in which to. keep his scale -when not in use.