1896 THE MICROSCOPE. 95 



set them on the shelf where the temperature was usually 

 very warm : 



Experiment No. 1. (Date, January 20, 1896).— Mix 8 

 ounces of flour and 4 pints of cold water, and stir till free 

 from lump ; add one-half ounce of pulverized alum, stir 

 thoroughly and place in the water bathand boil till of proper 

 thickness; then transfer to an earthenware jar, and when 

 cool stir in one-half ounce of a 40 per cent solution of form- 

 aldehyde. This has stood from the time made till May 10 

 in the jar, covered but not sealed, and at the present writ- 

 ing- I am using- this paste as sweet and in as good condition 

 as when first made. 



Experiment No. 2. — Take of gelatin, 1 ounce; flour, 4 

 ounces; water, 3 pints; formaldehyde '8 ounce. Cover 

 the gelatin with one pint of water and allow it to soften, 

 then heat to dissolve, mix this with the flour and 2 pints of 

 water previously made into paste, and boil them. When 

 cool mix with formaldehyde. This paste at the end of 

 sixty days showed no signs of spoiling, being fresh and 

 sweet, although it had been exposed to a summer tempera- 

 ture all the time. Still it was necessary to keep it covered 

 when not in use. A portion that was left uncovered for a 

 week became watery. 



Experiment No. 3. — Mix starch, 2 ounces, and water 16 

 ounces, and make a paste by heating. When cool add j{ 

 ounce of formaldehyde. This was made on the same day 

 as No. 2 and subject to the same conditions. It is in per- 

 fect condition at the present writing. 



Experiment No. 4. — Mucilage of acacia, U. S. P., was 

 made and 1 per cent of formaldehyde added. This has 

 has now been standing for two months in a warm place 

 and shows no signs of fermentation. 



Experiment No. 5. — Make a thick paste from white dex- 

 trin, 4 ounces; and water, as much as required. Then 

 add iS ounces of flour paste made as in experiment No. 1, 

 and X ounce of formaldehyde. This has been setting on 

 the shelf for more then forty days and is as sweet as when 

 first made. 



Experiment No. (>. — To paste made as in No 5, but half 

 the quantity of formaldehyde was added. This kept 

 equally well. Thus it can readily be seen that by the use 

 of formaldehyde paste or mucilage can be kept for months. 

 — Western Druggist. 



