1716 Journal of Applied Microscopy 



] 



QUESTION BOX. 



Inquiries will be printed in this department from any inquirer. 

 The replies will appear as received. 



17. What is the method and formula for the sulpho-carbolate of zinc in 

 glycerol as a mountant, and for what is it particularly useful? — v. a. l.. 



18. Will any reader who has had practical experience give really reliable 

 formulae for decalcification fluids for teeth, so that the pulp is left in good con- 

 dition for study and staining ? — v. a. l. 



19. On p. 142*2, in Dr. Harris' formula for elastic stain, mercuric acid is given. 

 What is the synonym or formula for same ? Merck gives no such.— v. a. l. 



20. In formula for Harris' hrematoxylin solutions no agent is given to prevent 

 mould, which I find is very rapid and in quantity. — v. a. l. 



21. Will anyone state how the gas can be prevented from going out with 

 thermostat and burner under incubator? Just as soon as it steadies at 37°C. it 

 goes out, invariably within a short time.. If a Koch automatic burner is used, 

 as soon as it is steady the expanding coil cools so the arm drops and shuts off 

 the gas. The tube is attached to the main pipe from the meter. — k. e. p.. 



22. What is a simple method for the examination of blood for clinical pur- 

 poses, with special reference to counting the white cells, differential count, 

 estimating relative proportions, and obtaining color coefficient. Also what is 

 Hayem's method of expressing the amount of hemaglobin in normal red corpuscles 

 (per cent.) ? — j. h. w. 



23. Referring to Dr. Goldhorn's new blood stain, reviewed on page 1635 of 

 the Journal, the following questions have been asked : 



id) Should the solution be made up to any definite quantity after evapora- 

 tion, or is it the intention to evaporate it down to concentration ? 



(/') Is it better to decant from the thick sediment before attempting to 

 neutralize the reaction ? 



(r) Is not the sediment composed largely of lithium carbonate, which 

 would prolong the operation of acidification if left in ? 



{d) After bringing the solution to an acid reaction, is it better to neutralize 

 with the powdered lithium carbonate or the solution ; in other words, is there 

 any point in keeping the solution nearly at saturation, or will it act just as well 

 if somewhat diluted during the process of correcting the reaction ? 



{e) Is there any objection to filtering after the reaction is corrected ? — e. h. b. 



REPLY TO QUESTION No. 23. 



{a) As to quantity : Make 300 c.c. if you use an ordinary small water bath 

 heated by a single Bunsen burner. 



{b) As to decanting: Yes, decant ; or, better still, run through cotton. 



if) As to the residue's nature : It is largely lithium carbonate ; get rid of 

 it as suggested, sub. 2. 



id') As to use of lithium : Use it in saturated solution ; you may dilute as 

 suggested in my description. 



ii) As to filtering : Do not filter through filter paper ; use some cotton in a 

 funnel. L. B. Goldhorn. 



