774 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Marcki sections in 2-4 hours. Sections are then washed in water, alcohol 

 and carbol-xylol. If overstating has taken place, or if the celloidin 

 is also stained, the sections should be immersed in • 5-1 p.c. hydrochloric 

 acid alcohol. This method can be employed with frozen, paraffin or 

 celloidin sections. 



Thermophore for use in Staining. — A. Hinterberger * describes a 

 •thermophore suitable for methods in which it is desirable to use the 

 staining solutions for periods of time. It consists of a box like a 

 Petri dish, 9 cm. in diameter and 4 cm. high. The lid has on its 

 upper surface a cup-shaped depression for holding the stain. The heat 

 is obtained by first filling the box with sodium acetate or barium hydrate, 

 and then adding cold distilled water. The uncovered dish will maintain 

 for an horn- a temperature of from 44° C. to 41° C, or from 54° C. to 

 51° C. respectively. In the covered dish the cold water poured in soon 

 becomes warm, and the temperature then sinks in about an hour and a 

 half from about 49° C. to U° C, or from 60° C. to 42° C. respectively. 

 The thermophore, filled with sodium acetate, ought to lie before use for 

 seven minutes in boiling water. If barium hydrate is used the longer 

 it is kept in boiling water the longer it will keep warm. 



C5) Mounting:, including: Slides, Preservative Fluids, &c. 



Soluble Glass as Mounting Medium for Examination of Paper.t 

 €. E. M. Fischer recommends soluble glass for mounting specimens of 

 paper fibres. The paper is first softened in warm distilled water and 

 then reduced to pulp. A piece is then teased out on a slide, and, after 

 the surplus water has been removed, the slide is then held over the 

 flame until just sufficient moisture remains to wet the preparation 

 evenly. A drop of thick soluble glass is placed on the fibres, and then 

 a cover-glass over all. The only inconvenience of this method is fre- 

 quency of air bubbles, but in other respects it is extremely advantageous. 



(6) Miscellaneous. 



Microscopical Examination of Paper.} — J. Hiibner states that it 

 is often of importance to ascertain microscopically the kind or kinds of 

 fibres from which a paper has been made. Pieces of the paper to be 

 examined, taken from various parts of the sheet, are boiled for 10-15 

 minutes in a weak solution of caustic soda (1 p.c). The boiled paper 

 is now placed on a fine sieve, washed free from soda. It is then trans- 

 ferred to a bottle containing garnets, and after a short shaking with 

 water, the pulp is drained and is then ready for examination. The 

 principal reagents required are iodopotassic iodide solution and iodozinc 

 chloride solution. The former turns linen, cotton and hemp, light to 

 dark brown ; straw and jute cellulose, grey ; wood cellulose and esparto, 

 partly grey, partly brown ; manila hemp, partly grey, partly brown, 

 partly yellowish brown ; wood pulp and raw jute, partly yellow, partly 

 yellowish brown. 



* Zeit. Wise. Mikr., xx. (1903) pp. 14-16. 

 t .Journ. App. Micr, vi. (1903) p. 2413. 

 X Journ. Soc. Arts, li. (1903) pp. 872-3. 



