20G ANNUAL OF SCIENTIFIC DISCOVERY. 



which they come in contact. So, also, when n-ed for anatomical injections, 

 the mercury permeates and blackens the tissues. 



My improvement greatly obviates these defects, and meets more perfectly 

 the requirements of alloys of this class. The composition composed of cad- 

 mium, lead, and tin, melts somewhat under 300 Fahrenheit, or 60 or 70 

 degrees below the melting point of the " fine solder" above referred to. It 

 is equal to it in malleability and tenacity, is much harder and stronger, and 

 admits of a higher polish. It ranks in fusibility with the more easily melted 

 " bismuth solders," and is believed to be greatly superior to any of them in 

 all the other requisites for this purpose. The advantages for other purposes 

 of a metal possessing these qualities will readily suggest themselves. 



The composition consisting of cadmium, lead, and tin, in conjunction with 

 bismuth, melts between 150 and 160 Fahrenheit, being some 50 or 00 

 below the melting point of Newton's " fusible metal," mentioned above, 

 corresponding very nearly with it in respect to malleability and tenacity, but 

 being harder and more adhesive. It is adapted to similar purposes ; and the 

 low temperature at which it fuses renders it applicable in many cases where 

 the other would not answer, while it is free from the objections appertaining 

 to the amalgams resorted to in such cases. As a material for anatomical 

 injections it will be found superior in every respect, it is believed, to the 

 amalgams in use. 



OX THE PROPERTIES OF CADMIUM. 



In a communication on the above subject to the editors of SiUiman's Jour- 

 nal, by Dr. Wood, of Nashville, Tennessee, the inventor of the new fusible 

 alloy, he says : 



The remarkable degree in which cadmium promotes the fusibility of com- 

 binations of lead and tin is especially worthy of note. The alloy of one to 

 two parts cadmium, two parts lead, and four parts tin, is considerably more 

 fusible than an alloy of one or two parts bismuth, two parts lead, and four 

 parts tin; and when the lead and tin are in larger proportion, the effect is 

 svill more marked. It takes less cadmium to reduce the melting point a 

 certain number of degrees than it requires of bismuth, besides that the 

 former does not impair the tenacity and malleability of the alloy, but 

 increases its hardness and general strength. Bismuth has always held a 

 preeminent rank among metals as a fluidifying agent in alloys. Its remark- 

 able property of "promoting fusibility" is specially noted in all our works 

 on chemistry. But I do not find it intimated in any that cadmium ever 

 manifests a similar property. The fact, indeed, appears to have been wholly 

 overlooked, owing perhaps to the circumstance that as an alloy with cer- 

 tain metals cadmium does not promote fusibility. 



Cadmium promotes the fusibility of some metals, as copper, tin, lead, 

 bismuth; while it does not promote the fusibility of others, as silver, anti- 

 mony, mercury, etc. (/'. e., does not lower the melting point beyond the 

 mean). Its alloy with lead and tin in any proportion, and with silver and 

 mercury withjn a certain limit, say, equal parts, and especially if two parts 

 silver and one of cadmium, or two parts cadmium and one mercury, are 

 used, are tenacious and malleable; while its alloys with some malleable 

 metals (irold, copper, platinum, etc.), and probably with all brittle metals, 

 arc brittle. 



