APPENDIX I. 543 



Eubber corks and tubing of exceptionally good quality, made from Para 

 rubber, are supplied by BENDER and HOBEIN, Munchen, Gabelsberger 

 Str. 76a. 



Platinum crucibles, etc. : HERAUS, Hanau. 



Horn and porcelain apparatus of all kinds : EPHKAIM GREINER, Stiitzer- 

 bach, Thuringia. 



Glass goods of all kinds (tubes, beakers funnels, etc.): ALT EBERHARDT 

 und JAGER, Ilmenau, Thuringia, and EPHRAIM GREINER, Stiitzerbach, 

 Thuringia. 



Burettes, pipettes, wash-bottles, gas preparation apparatus, etc.: Dr. R. 

 MUENCKE, Berlin, N.W., Luiseiistrasse 58. 



Mills for grinding seeds, bark, etc. : GRUSON, Magdeburg-Buckau, or 

 WENDEROTH, Cassel. 



Presses and straining cloths : G. WENDEROTH, Cassel, and GEISSLER NACHF. 

 F. MULLER, Bonn. 



Specially good syphon barometers are supplied by GEISSLER NACHF. F. 

 MULLER, Bonn. The instrument may be fixed on a stand, by means 

 of which, when not in use, it can be inclined. The glass is thus 

 always kept clean in the region where the readings take place. 



.Reservoir barometers of specially good quality, with stand and ther- 

 mometer, are supplied for 32 mks., by W. HAAK, glass-blower, Jena. 



Stands of all kinds are to be obtained from DESAGA, Heidelberg. Stands 

 having a porcelain base, and specially suitable for immersion in 

 water, are supplied by BUHLER, Tubingen. 



Apparatus for Nitrogen determinations after Kjeldahl's method: ALT 

 EBERHARDT und JAGER, Ilrnenau, Thuringia. 



Mirror galvanometers are to be obtained from the mechanical workshops 

 of Dr. TH. EDELMANN, Munchen, and H. MEYER, Zurich. The latter 

 firm supplies somewhat cheaper, but still very sensitive apparatus. 

 The mirror galvanometers, after Hermann, turned out by PLATH, 

 Potsdam, are also specially to be recommended. The instrument, 

 provided with two coils of 30,000 turns in all, two thermocoils of 100 

 turns each, excellent damping arrangement, telescope, and scale, 

 costs 485 mks. 



Spectral apparatus of various kinds are to be obtained of GEISSLER NACHF. 

 F. MULLER, Bonn. A large Hofmann spectroscope, with comparison 

 prism and measuring arrangement, costs 240 mks. A. Kituss, 

 Hamburg, also supplies very good instruments. Very satisfactory 

 pocket spectroscopes, provided with a scale, are to be obtained for 

 60 mks. from SCHMIDT and HAENSCH, Berlin, Stallschreiberstrasse 4. 



Air pumps, suction pumps, etc., are to be obtained from Dr. MUENCKE, 

 Berlin. The Arzberger water current pump, by means of which 

 very complete exhaustion may be attained, is specially to be 

 recommended. It can be obtained for 30 mks. from C. GERHARDT, 

 in Bonn ; and is supplied also by Dr. MUENCKE, Berlin ; and of the 

 highest quality by PAUL BOHME, Briinn. I further recommend very 

 strongly the water current pump supplied by HILDEBRAND, glass- 

 blower, Erlangen. The small apparatus (price 2 mks.) is fixed by 

 means of very thick rubber tubing to the water tap. The ex- 

 haustion is very complete, approaching the tension of aqueous 

 vapour. 



