14 General Martin Field on [Jan. 



and this is the reason why its specific gravity is so high as 1*22, 

 When I spoke of muriatic acid in my work, I meant pure acid, 

 and I have never been able, even in winter, to obtain it higher 

 than 1-212. 



I have now noticed every thing in the review that seems to 

 me entitled to attention, or likely to mislead the young chemist, 

 I shall conclude by observing that in my late work I have given 

 747 sets of experiments, most of them analyses, a considerable 

 proportion of which are new, and all were performed in the 

 College laboratory of Glasgow, either by myself or my pupils 

 under my immediate directions and superintendence. A very 

 considerable proportion of these analyses were repeated many 

 times before 1 felt satisfied with the result. This labour, the 

 greatest hitherto undertaken by any individual chemist, occu- 

 pied the whole of my attention for five years, during the greatest 

 part of which time I was as assiduously employed as any journey- 

 man in Glasgow. Now let us sum up the result of Dr. Ure's 

 animadversions. He affirms (without assigning any reason for 

 his statement) that three of my analyses are erroneous, that three 

 are fictitious, and that I have stolen three from his own imma- 

 culate publications. Now were we to grant the truth of this 

 impudent and most profligate statement, it would still follow, 

 even by his own showing, that 735 of my analyses are perfectly 

 accurate. 



Article II. 



Oh the Origin of Ergot. By General Martin Field.* 



As to the origin and nature of ergot, various opinions and 

 theories have been adopted ; but the three following have 

 appeared the most plausible, and have been the most strenuously 

 supported. First : among the French, Tissot and others affirm, 

 " that ergot, or spurred rye, is such as suffers an irregular vege- 

 tation in the middle substance between the grain and the leaf> 

 producing an excrescence ;" and that this morbid change i$ 

 produced by the extremes of humidity and heat of the season. 



Second : In England it has been the opinion of some, " that 

 ergot is an excrescence, caused by the sting and deposition of 

 the ego's of an insect." 



And third : Others affirm, " that it is a parasitic Fwj/gMS, like 

 the different sorts of blight, smut, &c." 



I shall not attempt to support or oppose either of the opinions 

 above-mentioned ; but shall relate such facts as have fallen 

 under my view, without regard to any theory upon the subject. 



The field of rye in which I made ray observations was within 

 fifty yards of my house, which afforded me an opportunity of 



* American Journal of Science. 



