Mr Johnston's Visit to Berzelitis. 199 



the labour of weighing much ; each arm is divided into ten 

 equal parts. It is the principle of- the steelyard first applied 

 to the common balance by Gahn, so that, when you come near 

 the equipoise, you can balance completely, and estimate your 

 weight to the most minute fraction, without changing your 

 weight, simply by moving your last millegramme backwards 

 or forwards on the arm. Those leaden weights in the drawer 

 are likewise intended to abridge labour. 'They are ^xact coun- 

 terpoises for all his crucibles and other small platinum vessels, 

 so that any of them may be balanced almost immediatelyr 

 Open also those little boxes, and in the more or le^s minute 

 portions of gum lac attached to the weights, you will see evi- 

 dence of that nice adjustment without which the indications of 

 the most perfect balance were useless. Round this room are 

 arranged sets of drawers and glass-cases, containing apparatus, 

 tests and chemical preparations, all set aside and arranged with 

 the firreatest order and neatness. That other table beside the 

 window is fitted up for researches with the mouth blowpipe, on 

 which Berzelius has written so able a work. 



Turn now to the left, and through another doorway behold 

 him whom you have sought in vain in the two other apart- 

 ments. That is Berzelius. He is busy writing ; his table cover- 

 ed with journals, and his shelves groaning with books. You 

 see that little cabinet on his left. In the drawers of that little 

 cabinet are contained all his rarest chemical substances and 

 compounds, his Rhodium, Osmium, Selenium and their pre- 

 parations; his Fluorides, his Salts of Lithia, Yttria, Thorina, 

 with many other choice combinations to be met with no where 

 else, all of which he will not fail to show you — of some you 

 may even hope to become possessor. Now you may walk 

 forward and introduce yourself, secure of a welcome recep- 

 tion. ^Q 



Every thing in Berzelius's laboratory speaks of neatneJsSy 

 cleanliness and order. No bottles or dirty vessels scattered 

 about ; every thing is put away in its place ready to be laid 

 hold of when wanted. His arrangements for experiment are 

 of the simplest and neatest kind, and lie has many little ma- 

 chines for facilitating these arrangements, the merit of all 



1 



