move the growth of the Tree ^ fince every thing grows in prot 
portion to the Root beneath : But I am doubtful in this, whe- 
ther I do well or ill, and defire the judgement of others. For, 
I have heard from fome PlanterSj and afterwards from a Knight 
who had experience therein, that Roots cut fhort doebeft, as 
fending forth New roots^which draw fap and nourifliment beft. 
And we fee that Mojiles fet on flips that have no roots, come 
to a Tree (boner. And I have oft obferved, that a Moyk Tran« 
fplanted after it hath taken root does not live fo certainly, or 
thrive fo well as a flip newly fet* But I have gone beyond the 
bounds of a Letter. 
This Letter being imparted to an Ingenious Inquirer into fach 
things^ he vpos pleafed to return fome of his confiderations there* 
upon^whicb are liks puhlijlnd in our next. 
Some Obfervations^ touching Colours, in order to the Increafe of 
Dyes.^W/Ae Fixation of Colours --^ generoufly imparted by the 
Author of the Four above-mentioned Letters y^ho annexed them 
to that of IB Qbrmr* 15. 1670. 
TWo thingsjl conceive,are chiefly aimed at in the Inquiry 
of Colours^\^h\ch fubjeft you defire my thoughts of 5 the 
i?«e,to increafe the Materia Tiniforia^and the other ^to fix^xf poP' 
fible,thofe coIors,we either have already^or fhall hereafter dit 
cover for ufe.As to the /r/?,Animals and Vegetables,befides o- 
ther Natural Bodies , may abundantly furnifti us. And in 
both thefe kindsyS^^eColours areApparent.zs the various colours 
of Flowers^and the juices of fruits, &c. and the fanies of Ani- 
mals : others are Latent,and difcovered to us by the efiefts, the 
feveral Family's of Salt and other things may have upon them* 
Concerning the Apparent colors of Vegetables and Animals^and 
the various efFefts of different Salts in changing them from one 
colour to another 5 we have many Infliances in M^Bojile^ And if 
we might,with the good leave of that Honourable and Learned 
perfon, range them after our fafliionj we fliould give you at 
leaft a new Profpe(3:of them,and obferve to you tbeconformi* 
ty and agreement of the effefts of Salt on the divers parts of 
Vegetables; /^/jzs. i.That Acid Salts advance the colours of Flow- 
ers and Berries;>that isjaccording to the Experiments oiM.Boyle^ 
they make the i^ifefipns of BalauUium ox Pomgranat-Flowers, 
Red rofes, Glave-jilly flowersjMeferionjPcafe^bloom, Violets, 
Gyanus 
