388 Scientific Intelligence. [3H®f. 



lock are remarkably different, as is the colour both of the soluble 

 and feculent parts : it also possesses an extraordinary degree of 

 tenacity, a property which is not general!)' found in the common 

 extract ; and it abounds so much with crystallized matter as to 

 produce a gritty sensation when rubbed between the fingers. 

 The extract of belladonna contains a large quantity of crystals of 

 some kind of salt; but 1 have not/' says Mr. Barry, "succeeded 

 in procuring either of these in a separate state so as to give them 

 an examination. In some attempts to obtain them pure, and 

 more particularly to discover whether morphia was traceable in. 

 the extracts, I became acquainted with the singular fact, that, 

 phosphoric acid in a soluble state is to be found in all the 

 extracts. On further extending the investigation, it was ascer- 

 tained that this acid, besides that portion of it which exists as 

 phosphate of lime, is contained in a vast variety of vegetables. It 

 w r ould be foreign to the subject of this paper to enumerate the 

 substances that were tried; but I may just mention that all those 

 vegetables which are cultivated seem 10 contain phosphoric salt 

 in great abundance. 



• " The extract of taraxacum is another remarkable instance of 

 the difference in the sensible qualities of these preparations, 

 instead of being sweet to the taste, and high coloured, like 

 that prepared in the common way, it is bitter, and extremely pale, 

 when fresh made ; its taste much resembles that of the plant 

 itself. With respect to the strength of extracts made in vacua, 

 I have not. yet gained sufficient information to be able to present 

 a view of the relative proportions which they bear to the common 

 extracts ; but I have been informed by several medical friends 

 who have given them a trial that they find them materially 

 stronger. Perhaps some gentleman will consider the subject 

 sufficientlv deserving of investigation to collect such a state- 

 ment of cases as will enable him to present to the Society the 

 relative doses. I shall be glad to offer for the acceptar.ee of 

 such, specimens of any kind which they may be inclined to make 

 use of." 



There is nothing new in the principle upon which Mr. Barn's 

 apparatus acts. The patent is founded upon the method of 

 forming a vacuum by means of steam, and of maintaining it by 

 immersing the whole under water; hence the apparatus, from it* 

 being thus rendered easy of management, and less expensive, ap- 

 peared likely to be employed in other manufactures, such as sugar 

 refining, and colour making. " Chemists, therefore," says Mr. B. 

 " who are desirous of inspissating extracts in vacuo are at liberty 

 to do it in any apparatus differing from that which has been made 

 the subject of my patent, and thus these substances may con- 

 tinue the objects of fair competition as to quality and price." 



The following observations and sketch will convey an idea' of 

 the form and mode of operation of Mr. Barry's apparatus. 



" The mode of procuring the vacuum, and the manner of iuaji£- 



