Part 21 (1/2)
If _c_ = weight of composition taken, _d_ = ” ” filter paper, _a_ = ” after first extraction, _b_ = ” ” second extraction, then _c+d-a_ = weight of fulminate, _c+d-a-b_ = ” ” KClO_{3}, _b-d_ = ” ” sulphide of antiate mortar
The results of the analysis by this iven below--
________________________________________________________________________ | | | | | | A | B | | | | | | | Percentage | Percentage | Percentage | Percentage | | | Taken | Found | Taken | Found | |____________________|____________|____________|____________|____________| | | | | | | | Antimony Sulphide | 3647 | 3625 | 3734 | 3722 | | Potassium Chlorate | 3325 | 3371 | 4603 | 4643 | | Mercury Fulminate | 3027 | 3002 | 1661 | 1634 | |____________________|____________|____________|____________|____________|
Dr HW Brownsdon's (_Jour Soc Chem Ind_, xxiv, April 1905) process is as follows:--The cap co the cap with pliers, while held over a porcelain basin of about 200 cc capacity, and re the loosened foil and broken composition byto the shell or foil is loosened by alcohol, and washed into the dish by means of alcohol in a small wash bottle The shell and foil are put to one side and subsequently weighed when dry The composition in the dish is broken down quite fine with a flat-headed glass rod, and the alcohol evaporated on the water bath till the residue is moist, but not quite dry, 25 cc of water are then added, and the composition well stirred frorm of pure sodium, thiosulphate, the contents of the dish, is well stirred for two and a half e is then added, and the solution titrated with N/20 sulphuric acid, which has been standardised against weighings of 005-01 grm fulminate to which 25 cc
of water is added in a porcelain dish, then 05 gr for two and a half minutes, titrated with N/20 sulphuric acid The small amount of antinition of the end point After titration, the solution is filtered through a small 5-1/2 cm filter paper, which retains the anti the Sb_{2}S_{3} is ashed and then transferred to a large 6 by 1 test tube Five cc of strong hydrochloric acid are added, and the contents of the tube boiled gently for a few seconds until the sulphide is dissolved and all the H_{2}S driven off or decomposed: 2-3 cc of a saturated solution of tartaric acid are added, and the contents of the tube washed into a 250 cc Erlenmeyer flask The solution is then nearly neutralised with sodium carbonate, excess of bi-carbonate added, and after the addition of some starch solution titrated with N/20 iodine solution This method for small quantities of stibnite is both quick and accurate, the error being about 00003 grm Sb_{2}S_{3} at the outside
The tendency of this ures for the fulible error, it does not affect the value of the results as a criterion of unifor test results were obtained by Dr Brownsdon:--
____________________________________________________________ | | | | | Fulminate Taken | Fulminate Found | Error | | Grm | Grm | Grm | | | | | | 00086 | 00083 | -00003 | | 00082 | 00081 | -00001 | | 00074 | 00071 | -00003 | | 00068 | 00066 | -00002 | |____________________|___________________|___________________| | | | | | Stibnite Taken |Sb_{2}S_{3}, Found| Error | | Grm | Grm | Grm | | | | | | 00085 |00084 | -00001 | | 00098 | 00099 | +00001 | | 00160 | 00157 | -00003 | | 00099 | 00100 | +00001 | |____________________|___________________|___________________|
TABLE FOR CORRECTION OF VOLUMES OF GASES FOR TEMPERATURE, GIVING THE DIVISOR FOR THE FORMULA
V_{1} = V x B/(760 x (1 + dt)) (d = 0003665) 1 + dt from 0 to 30 C
___________________________________________________________ | | | | | t | 760x(1+dt) | t | 760x(1+dt) | t | 760x(1+dt)
_____|_____________|_____|_____________|_____|_____________ | | | | | C | | C | | C | 00 | 750000 | 17 | 7647352 | 34 | 7694704 1 | 7602785 | 8 | 7650137 | 5 | 7697489 2 | 7605571 | 9 | 7652923 | 6 | 7700274 3 | 7608356 | 20 | 7655708 | 7 | 7703060 4 | 7611142 | 1 | 7658493 | 8 | 7705845 5 | 7613927 | 2 | 7661279 | 9 | 7708631 6 | 7616712 | 3 | 7664064 | 40 | 7711416 7 | 7619498 | 4 | 7666850 | 1 | 7714201 8 | 7622283 | 5 | 7669635 | 2 | 7716987 9 | 7625069 | 6 | 7672420 | 3 | 7719772 10 | 7627854 | 7 | 7675206 | 4 | 7722558 1 | 7630639 | 8 | 7677991 | 5 | 7725343 2 | 7633425 | 9 | 7680777 | 6 | 7728128 3 | 7636210 | 30 | 7683562 | 7 | 7730914 4 | 7638996 | 1 | 7686347 | 8 | 7733699 5 | 7641781 | 2 | 7689133 | 9 | 7736485 6 | 7644566 | 3 | 7691918 | 50 | 7739270 _____|_____________|_____|_____________|_____|_____________ ___________________________________________________________ | | | | | t | 760x(1+dt) | t | 760x(1+dt) | t | 760x(1+dt)
_____|_____________|_____|_____________|_____|_____________ | | | | | C | | C | | C | 51 | 7742055 | 9 | 7875755 | 7 | 8009454 2 | 7744841 |100 | 7878540 | 8 | 8012239 3 | 7747626 | 1 | 7881325 | 9 | 8015025 4 | 7750412 | 2 | 7884111 |150 | 8017810 5 | 7753197 | 3 | 7886896 | 1 | 8020595 6 | 7755982 | 4 | 7889682 | 2 | 8023381 7 | 7758768 | 5 | 7892467 | 3 | 8026166 8 | 7761553 | 6 | 7895252 | 4 | 8028952 9 | 7764339 | 7 | 7898038 | 5 | 8031737 60 | 7767124 | 8 | 7900823 | 6 | 8034522 1 | 7769909 | 9 | 7903609 | 7 | 8037308 2 | 7772695 |110 | 7906394 | 8 | 8040093 3 | 7775480 | 1 | 7909179 | 9 | 8042879 4 | 7778266 | 2 | 7911965 |160 | 8045664 5 | 7781051 | 3 | 7914750 | 1 | 8048449 6 | 7783836 | 4 | 7917536 | 2 | 8051235 7 | 7786622 | 5 | 7920321 | 3 | 8054020 8 | 7789407 | 6 | 7923106 | 4 | 8056806 9 | 7792193 | 7 | 7925892 | 5 | 8059591 70 | 7794978 | 8 | 7928677 | 6 | 8062376 1 | 7797763 | 9 | 7931463 | 7 | 8065162 2 | 7800549 |120 | 7934248 | 8 | 8067947 3 | 7803334 | 1 | 7937033 | 9 | 8070733 4 | 7806120 | 2 | 7939819 |170 | 8073518 5 | 7808905 | 3 | 7942604 | 1 | 8076303 6 | 7811690 | 4 | 7945390 | 2 | 8079089 7 | 7814476 | 5 | 7948175 | 3 | 8081874 8 | 7817261 | 6 | 7950960 | 4 | 8084660 9 | 7820047 | 7 | 7953746 | 5 | 8087445 80 | 7822832 | 8 | 7956531 | 6 | 8090230 1 | 7825617 | 9 | 7959317 | 7 | 8093016 2 | 7828403 |130 | 7962102 | 8 | 8095801 3 | 7831188 | 1 | 7964887 | 9 | 8098587 4 | 7833974 | 2 | 7967673 |180 | 8101372 5 | 7836959 | 3 | 7970458 | 1 | 8104175 6 | 7839544 | 4 | 7973244 | 2 | 8106943 7 | 7842330 | 5 | 7976029 | 3 | 8109728 8 | 7845115 | 6 | 7978814 | 4 | 8112514 9 | 7847901 | 7 | 7981600 | 5 | 8115299 90 | 7850686 | 8 | 7984385 | 6 | 8118084 1 | 7853471 | 9 | 7987171 | 7 | 8120870 2 | 7856257 |140 | 7989956 | 8 | 8123655 3 | 7859042 | 1 | 7992741 | 9 | 8126441 4 | 7861828 | 2 | 7995527 |190 | 8129226 5 | 7864613 | 3 | 7998312 | 1 | 8132011 6 | 7867398 | 4 | 8001098 | 2 | 8134797 7 | 7870184 | 5 | 8003883 | 3 | 8137582 8 | 7872969 | 6 | 8006668 | 4 | 8140368 _____|_____________|_____|_____________|_____|_____________ ___________________________________________________________ | | | | | t | 760x(1+dt) | t | 760x(1+dt) | t | 760x(1+dt)
_____|_____________|_____|_____________|_____|_____________ | | | | | C | | C | | C | 195 | 8143153 |230 | 8240642 | 5 | 8338131 6 | 8145938 | 1 | 8243427 | 6 | 8340916 7 | 8148724 | 2 | 8246213 | 7 | 8343702 8 | 8151500 | 3 | 8248998 | 8 | 8346487 9 | 8154925 | 4 | 8251784 | 9 | 8349273 200 | 8157080 | 5 | 8254569 |270 | 8352058 1 | 8159865 | 6 | 8257354 | 1 | 8354843 2 | 8162651 | 7 | 8260140 | 2 | 8357629 3 | 8165436 | 8 | 8262925 | 3 | 8360414 4 | 8168222 | 9 | 8265711 | 4 | 8363200 5 | 8171007 |240 | 8268496 | 5 | 8365985 6 | 8173792 | 1 | 8271281 | 6 | 8368770 7 | 8176578 | 2 | 8274067 | 7 | 8371556 8 | 8179363 | 3 | 8276852 | 8 | 8374341 9 | 8182149 | 4 | 8279638 | 9 | 8377127 210 | 8184934 | 5 | 8282423 |280 | 8379912 1 | 8187719 | 6 | 8285208 | 1 | 8382697 2 | 8190505 | 7 | 8287994 | 2 | 8385483 3 | 8193290 | 8 | 8290779 | 3 | 8388268 4 | 8196076 | 9 | 8293565 | 4 | 8391054 5 | 8198861 |250 | 8296350 | 5 | 8393839 6 | 8201646 | 1 | 8299135 | 6 | 8396624 7 | 8204432 | 2 | 8301921 | 7 | 8399410 8 | 8207217 | 3 | 8304706 | 8 | 8402195 9 | 8210003 | 4 | 8307492 | 9 | 8404981 220 | 8212788 | 5 | 8310277 |290 | 8407766 1 | 8215573 | 6 | 8313062 | 1 | 8410551 2 | 8218859 | 7 | 8315848 | 2 | 8413337 3 | 8221144 | 8 | 8318633 | 3 | 8416122 4 | 8223930 | 9 | 8321419 | 4 | 8418908 5 | 8226715 |260 | 8324204 | 5 | 8421693 6 | 8229500 | 1 | 8326989 | 6 | 8424478 7 | 8232286 | 2 | 8329775 | 7 | 8427264 8 | 8235071 | 3 | 8332560 | 8 | 8430049 9 | 8237857 | 4 | 8335346 | 9 | 8432835 | | | |300 | 8435620 _____|_____________|_____|_____________|_____|_____________
CHAPTER VIII
_FIRING POINT OF EXPLOSIVES, HEAT TESTS, &c_
Horsley's Apparatus--Table of Firing points--The Government Heat-Test Apparatus for Dynamites--Nitro-Glycerine, Nitro-Cotton, and Sulator for Heat-Test Apparatus--Specific Gravities of Explosives--Table of Te Point of Explosives~--The firing point of an explosive may be determined as follows:--A copper dish, about 3 inches deep, and 6 or more wide, and fitted with a lid, also of copper, is required The lid contains several small holes, into each of which is soldered a thick copper tube about 5 er one in the centre in which to place a thermometer The dish is filled with Rose'sto the probable te point is then taken thus:--After putting a little piece of asbestos felt at the bottom of the centre tube, the thermometer is inserted, and a small quantity of the explosive to be tested is placed in the other holes; the lid is then placed on the dish containing the melted paraffin or metal, in such a way that the copper tubes dip below the surface of the liquid; the temperature of the bath is now raised until the explosive fires, and the temperature noted The initial temperature should also be noted
THE FIRING POINT OF VARIOUS EXPLOSIVES (by C E Munroe)
(Horsley's Apparatus used)
_____________________________________________________________________ | | C
Nitro-glycerine, 5 years old (a single drop taken) | 203-205 Gun-cotton (coun-cotton, stored for 4 years | 179-187 Ditto, stored for 1 year | 187-189 Air-dried collodion-cotton, long staple ”Red Island | cotton,” 3 years old | 186-191 Air-dried collodion, 3 years old, stored wet | 197-199 Hydro-nitro-cellulose | 201-213 Kieselguhr dynaelatine | 203-209 Mercury fulminate | 175-181 Gunpowder (shell) | 278-287 Hill's picric powder (shells) Been in store 10 years | 273-283 Ditto (musket) Composed of-- | 282-290 Ammonium picrate 4218| Potassium picrate 5379 ” | Charcoal (alder) 385 ” | ________ | | 9982 | Forcite, No 1 | 187-200 Atlas powder (75 NG) | 175-185 Eazine for some months in | a wooden box | ” No 2 Stored in tin case | 165-177 ” No 5 ” ” | 205-217 __________________________________________________________|__________ | | | C | Powder used in Chassepot rifle | 191 | By Leygue & Chaunpowder | 295 | ” ”
Rifle powder (picrate) | 358 | ” ”
Cannon | 380 | ” ”
__________________________________|_________|________________________
Horsley's apparatus consists of an iron stand with a ring support, holding a hemispherical iron vessel or bath in which solid paraffin is put Above this is another movable support, from which a thermometer is suspended, and so adjusted that its bulb is immersed in the e-case, 5/8 inch in dia, is suspended over the bath by le, so that the end of the case is just 1 inch below the surface of thethe firing point of any explosive, thepoint; the thermometer is inserted in it, and a minute quantity of the explosive is placed in the bottoe-case The initial te the explosive is inserted in the bath The tee-case flash off or explode, when the te point_
[Illustration: FIG 46--HEAT TEST APPARATUS]