1680 



Journal of Applied Microscopy 



The extract should of course be free from 

 any outside source of contamination, hence the 

 method of obtaining it is highly important. 

 For obtaining large amounts of extract, the 

 common tincture presses are of service, but 

 where a small amount or part of a plant is all 

 that can be used, or where only a small amount 

 of juice or extract is desired, the tincture press 

 is of no particular service. 



In the course of a special investigation, the 

 author found it necessary to devise an appa- 

 ratus for extracting a small amount of juice 

 or sap from parts of plants. Since some little 

 ^Z difficulty was experienced in finding a suitable 



„. „ r t . • • 1 • ■ apparatus, it will be described here, as it may 



Fig. I. Press for obtaining plant juice, rr ' ' j 



be of service to others. 

 For the power, the frame and screw of a medium sized tincture press were 

 employed as shown in the diagram. The wooden block (a) carries a 50 mm. 

 porcelain funnel (b) with vertical sides and perforated bottom. The opening 

 in the block was made of the same form as the funnel, so that the funnel would 

 be held firmly in position and would also stand a considerable amount of pressure. 

 The pressure is applied by means of the screw on the wooden disc (c), which is 

 made to fit loosely in the end of the funnel. The parts of the plant from which 

 the extract is to be made must first be cut or ground fine. This can easily be 

 accomplished by means of a small Enterprise food-chopper. By this means it 

 was possible to obtain, with comparative ease, a few cubic centimeters of extract 

 or a larger amount if desired. F. D. Heald. 



Parsons College. 



Ink for Writing on Glass. 



During a recent visit to some of the foreign laboratories I found in use in 

 the laboratory of the University of Berne an ink for marking on glass which is 

 so satisfactory that I have adopted it for use in the laboratory with which I am 

 connected. It consists of a mixture of three parts of a 13 per cent, solu- 

 tion of shellac in alcohol in the cold with five parts of the same strength solution 

 of borax in distilled water. The solutions should be mixed a drop at a time, and 

 if a precipitate forms the mixture may be heated until clear. Enough methylen 

 blue should be added to color it a deep blue. This makes one of the handiest 

 inks for laboratory use, for with it notes can be made on glassware, slides, etc., 

 which dry quickly and remain. Either a sharp pointed stick or a pen can be 

 used to apply it. It is far handier than using gummed labels and writes better 

 than the Faber pencil made for the same purpose. It will wash off afterwards. 



Detroit. Wm. R. HuBBERT. 



