Of other glass having a linear co-efficient of expansion not exceeding

70.17 - Laboratory, hygienic or pharmaceutical glassware, whether or not graduated or calibrated. - Of fused quartz or other fused silica 7017.20 - Of other glass having a linear coeficient of expansion not exceeding 5 x 7017.10 per Kelvin within a temperature range of 0 "C to 300 OC 7017.90 - Other I This heading covers glass articles of a kind in eneral use in laboratories research, pharmaceutical, industrial, etc.), includin special bott es (gas washing, reagent, Wou fs, etc.), s ecial tubes (gas washing, drymg, con ensation, filter, gas burettes, test-tubes, etc.), stirrers, $stilling, flasks, graduated jars, culture flasks Kolle, Roux, etc.), burettes of all kinds, evaporating dishes, volumetric flasks, s ecial be1 -jars and receivers (vacuum, necked, etc.), s ecial dropping bottles (calibrated, etc?, retorts, crystallisin dishes, drying cylinders, filter p ates and discs, s oons, desiccators, dialysers, adapters, con ensers, receivers for distillation apparatus, special k e l s (with stop-cock, bulb-shaped funnels, etc.), cylinders, crucibles, filter crucibles, special flasks (conical, multi-necked, etc.), special s irit burners, mortars, weighing boats, pipettes, vacuum vessels of various specialized types g o t falling in heading 96.17), wash-bottles, sto -cocks, spatulas, ars (filtering, precipitating, multinecked, etc.), muffles, crucible support p ates, microscope s ides and cover glasses, etc. K 'f I % ! Reference should be made to Explanatory Note to heading 90.27 for the rules governing the classification of instruments and a aratus for physical or chemical analysis which, though potentially covered by heading 9 0 . 8 myat the same time be taken to be laboratory glassware within the meaning of this heading. Such reference will show that this heading covers for exam ley acidimeters (other than those of heading 90.25), galactometers, butyrometers, lacto utyrometers, and similar instruments for testing dairy products; albumenometers and ureometers; eudiometers; volumenometers, nitrometers, K$ps and Kjeldahl a paratus and the like; calcimeters; cryoscopes and ebullioscopes for detemimng molecular weigts, etc. # The expression "hygienic or pharmaceutical glassware " refers to articles of general use not inter alia, irri ators, requirin the services of a practitioner. The nozzles ?for syringes, enemas, etc.), urinals, cupping-g asses, breast-relievers with or without rubber bulb), depressors. Spools and reels or winding surgical catgut are also included. f Articles of this heading may be graduated or calibrated. They may be made of ordinary lass (particularly for pharmaceutical or hygienic oses), but laboratory glassware is fre uent y of borosilicate glass, hsed quartz or other fuse si ica because of the greater chemical sta ility and low coefficient of expansion of such glass. BY a The heading excludes (a) Containers for the conveyance or packing of goods (headin 70.10); ordinary curved watch glasses sometimes used in the laboratory (headbg 70.15, see ffieExp, anatory Note to that heading); chemists' special display bottles and glassware of a kind used for industrial purposes (heading 70.20). f (b) GIass instruments and appliances of Chapter 90, for example, hypodermic syringes, special cannulae and other articles berng medical, surgical, dental or veterinary instruments or appliances (heading 90.18); hydrometers and similar floating instruments, thermometers, pyrometers and barometers of heading 90.25, instruments and apparatus of heading 90.26 (for measuring or checking fluid flow, etc.) and instruments and apparatus for physical or chemical analysis, etc., of heading 90.27.