18981 MICROSCOPICAL JOURNAL. SI 



he covers the spot with a coating- of sand rac varnish. If 

 the injury has been very considerable he repeats the oper- 

 ation on the opposite side of the paper. This varnish 

 ^ives the paperback, to a larg-e extent, restores the paper 

 to its natural appearance, and, besides, g-ives it a surface 

 upon which he can write or print without fear of the ink 

 spreading-. The fig-ure put in the place of the one erased 

 does not rest on the paper, however, but on the layer of 

 varnish, and on this fact rests our ability to remove the 

 counterfeit figure without interfering- with the g-enuine 

 ones that remain. An application of the second fluid effaces 

 the printed figure. In this manner Mr. Blarez has suc- 

 ceeded in demonstrating- some of the cleverest forg-eries. 



New Use for Paraffin.^ — Some chewing- g-um on sale in 

 Eng-land and containing- paraffin was labelled "for chewing- 

 only; not to be eaten". One child died of peritonitis after 

 swallowing some of this gum. 



To Cut Ring. — Through a square piece of wood pass 

 three pins; one in the center projecting a trifle further 

 than the other two. That one acts as a central pivot while 

 the other two are cutters. If a handle is fixed to the wood 

 and the long pin made to pierce the celluloid or other sub- 

 stance to be cut, the tool can be revolved around this cen- 

 tral pivot and the cutting- pins which are placed at a proper 

 distance for the center will describe circles. The radius 

 of the circle to be cut will determine the distance from the 

 central pin to the cutters. Ring-s may be made in this way 

 in large numbers without expense. If the substance being- 

 cut up is too thick, cut partly throug-h, turn it bottom side 

 up, insert the pivot pin in the hole already made and cut 

 till you meet the former circular cutting- which you are 

 sure to do with exactness if care is used. 



Tobacco Seeds. — Last summer an Agassiz student saved 

 and weig;-hed the seeds from a single pod. The weig-ht 

 came to 44.304 grammes. By count and weight it was 

 found the one hundredth of . gramme contained 450 or, 

 that one weighs .00002 of a gramme. Hence the 44 and 

 more grammes contained 1,993,680 seeds. 



