446 IMr. G. Gore on the Properties of 



antimony deposited upon perfectly similar copper wires, that the 

 amorphous variety M'as electro-positive to the crystalline in the 

 following liquids : — dilute phosphoric, suljihuric, hydrochloric, 

 and nitric acids ; in aqueous solutions of ammonia, potash, and 

 carbonate of soda; also in the first-mentioned chloride solution. 

 This difference of electric condition was in some instances of de- 

 position so great as to generate a separate electric current, and 

 completely redissolve some of the dark portions. The })ha;no- 

 raenon of lateral surface deposit did not occur in the tartaric- 

 acid solution. Antimony trees, consisting of branches of amor- 

 phous and crystalline nodules, were easily formed by suspending 

 a horizontal copper wire as a cathode upon the surface of the 

 terchloride solution. 



15. Heat was perceptibly evolved in the first-named liquid 

 during deposition ; on one occasion, with a feeble battery, when 

 the external air was at 66° Fahr., the coldest part of the liquid, 

 viz. behind the anode, was at 67°"5 Fahr., and the warmest part 

 in front of the anode 71° Fahr. And on another occasion, with 

 a stronger battery (consisting of twenty-four pairs of zinc and 

 silver plates) weakly excited, with an anode of moderate size, a 

 thermometer in contact with the front of the anode rose from 

 74"-5 to 87°-5 Fahr. 



16. Faint crackling sounds, audible at about 4 or 5 feet distant, 

 frequently occurred in the depositing liquid during the process; 

 they issued from the receiving surface, and appeared to be due 

 to alterations in the cohesive state of the metal, being generally 

 attended by the production of cracks, and occasionally of com- 

 plete rents in the metal ; they most frequently occurred when 

 the temperature of the deposit was changed by removal from the 

 liquid or by reimmersion. In one instance metallic sounds were 

 definitely traced to bubbles of gas suddenly expelled with force 

 from a small spot of a very firm deposit formed upon a bar mag- 

 net in the tartaric-acid liquid ; but no fissure or orifice was ob- 

 servable at the parts ; they were unattended by evolution of light. 



17. In common with electro-deposits generally, the inner and 

 outer surfaces of these deposits are in unequal states of cohesive 

 tension, frequently in so great a degree as to rend the metal ex- 

 tensively and raise it from the receiving surface during the pro- 

 cess in the form of a curved sheet with its concave side towards 

 the anode. This separation is very apt to occur in depositing 

 upon extended Hat surfaces, and does not often occur when the 

 form of the surface is unfavourable, as with wires, rods, bars, 

 &c., where the deposit extends around the mass, or where it 

 passes round projections, edges, &c., and retains a hold thereby. 

 This state of tension is most manifest in thin deposits, and espe- 

 cially iu the first-formed layer; for by depositing a thin layer 



